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Oh, thank you.
Thanks for showing up this morning,
I have to start with a story.
I'm impressed that the the
room is packed.
So I was playing in a rather
unsuccessful heavy metal band for quite
some years, and I always dreamed
about performing.
Life can be very ironic, you start
working on quantum computers and
diamonds and people show up to your
performance anyway.
So I have to start with a little
disclaimer, and I'm
I mean that from the bottom
of my heart.
I'm a physicist or more precisely,
I'm a material scientist.
And with that,
I have a strong background when it comes
to materials and diamonds.
My background is not so strong when it
comes to the things you are
interested in, quantum algorithms
and stuff. Although I will talk a little
bit about that.
Please be kind when it comes to the
question and to answer part of this
talk.
Anyway, let's start whenever
you take a look at the concepts
of future computers.
Of course, it makes sense to take a look
back on on the computers that were
there before.
And of course, every one of you know
this diagram, it's Moore's Law
and this diagram, it shows
this is the time scale and it shows
the numbers of transistors
on a microchip.
And this diagram never, never fails
to impress me because more
of he wrote a paper actually on that.
And he claimed that the number of
transistors will double every 24
month.
And he claimed that's 1965.
So back here, down here at a
time where we were only talking about a
few thousand
transistors and this law
is still true when it comes to the
to the more modern computers
where we have billions of transistors.
So that's quite impressive, this
vision that he had.
How is that possible or how could we
improve from a few thousand to two
billions of transistors on a on
a microchip?
Well, pretty straightforward
and pretty easily by scaling
down the size of the transistors.
Of course, if we take a look, this
is again, Moore's Law, the same.
But now I show you the feature
size, the transistor size, basically,
that you can find on on such microchips.
And we started in the 70s
with sizes of a few microns, 10
microns that would compare to
to your red blood cells, to the size
of your red blood cells.
And we are now down to 22
nanometers.
That's extremely small.
And we're closing in to sizes like
the diameter of your DNA, which is like
two nanometers thick or
wide.
How is that possible?
Well, it was possible
by simply scaling.
You had a technology, you had a
method of producing these transistors
and you slightly improved them.
And so you were able to reduce the
feature size.
Can can we go on like this
forever?
Obviously. No,
I actually believe we already have
seen the lowest limit that we
can reach. There was a work group
in 2012, I guess
they produced the transistor
made out of one single phosphorus
atom in a silicon
matrix
form.
At least for me, it's hard to believe
that we can get any smaller than one
single atom. I mean,
in the end, you need to to to store
the electron the the charge
carry somewhere.
So I think we we hit
bottom already.
But the problem is
not that that we will at one time,
really. I mean that was an
experiment in a laboratory that is
obviously not not
readily available microchip
yet, but still maybe we have seen
the lowest limit that we can reach.
But nevertheless, already
going there to the lowest limit
will
will make
us face some problems.
And these problems
will will arise here when
a future size gets even slower,
because then we have to deal later.
Then we have to deal with quantum effects
and what that means.
I want to show you on on the next slide
with an easy picture.
Again, let's start
with the German autobahn.
For those of you who are not coming
from Germany, German autobahn, so great
because you can drive as fast as you
want. And that is not a problem
as long as everybody stays on
the lanes, that is
or I should say, where you are supposed
to be. So if you are traveling
in that direction, you better stay
on the right side of the German autobahn.
If you are if you
are somehow able to
go over this barrier here in the middle
and.
Try to appear on this side,
you and your
opposite car drivers
will have some some problems.
Same is true, of course, for
microchips.
They are somehow or can be compared
to ultra bonds.
We have these electronically charged
carriers running around somewhere here
in this Connector's and stuff.
Transistors, as long as they stay where
we want them to be, everything is fine.
But as soon as we come
to really small sizes, small
scales, something really strange is
happening.
And this is a beautiful simulation
of John Christophe Benowa showing
you one electron.
This is this bluish, whitish thing
moving towards Syberia,
a barrier that this electron cannot
surpass.
And what you see here, most of the
electron is reflected are the
electron seems to be reflected.
But what you also can see is that a
small, whitish blob
is actually tunneling
through this area
where the electron is not supposed to
tunnel through.
So.
You see, when we come to small scales,
we are heading into problems because
electrons are freely jumping around and
that is not what we want.
So the question is, if we cannot avoid
quantum mechanics, why don't we use it?
Is there a way to use these effects?
And this is basically what I want
to talk today about.
My presentation is, is in two parts.
The first part is basic concepts
of quantum mechanics.
But there won't be any equations.
So I will stick to pictures and nice
metaphors and
the parts will be a real realization
of quantum computers, how we try
to do this with diamonds.
OK, I promised you pictures.
So we start with this picture.
Manolo Noya, I love him dearly.
He made us world champion,
but I also envy him a bit
because the game he's playing is fairly
simple while I'm dealing
with quantum mechanics.
And that's fairly not simple.
And this guy is learning, earning
much more money than me.
I don't have I not
even have a permanent position at the
university. But anyway, let's let's
take a look at classical soccer.
Manolo Noya, easy game.
He needs to information to play this easy
game. He needs to know where the ball is.
So he needs to know where is the position
of the ball.
And he needs to know where is the
ball going.
So the velocity, that's what physicists
call it, velocity of the ball.
So that means speed and direction.
So to information, very easy
game.
Now we go to quantum soccer.
That's harder manual
now needs to choose whether or
not she wants to know the position,
then you don't know.
Absolutely don't know where the ball is
going
or he chooses to know where the ball
is going, then he has no
idea where the ball is.
You see, the game is getting harder.
No World Cup for us in
the case of soccer.
So being
more precise now,
we can compare it now.
We can compare classical physics
now with quantum physics
as we have seen classical physics.
So if we are talking about balls, it's
perfectly fine that we know the position
and the velocity of a particle
that's that changes with quantum
quantum physics.
Let's go back to the electron.
You see here, this bluish reddish
electron. And we know
let's say we know exactly the velocity
of the of the particle.
We know where it is going and which
speed. Then we don't know the
position of the electron, actually.
So this is not how our physicists
would draw it.
We like diagrams.
So we would do something like this here.
The X axis is the position
of the electron. The W here
means the probability that the electron
is actually at that point.
So it is very likely
that it's somewhere here.
But there's still the chance that is
right of there or left of there.
So it can be somewhere here with
more or less probability.
Werner Heisenberg, German physicist,
was working on that was a founder
of this theory.
And this is Heisenberg's uncertainty
principle. That simply means the
uncertainty of the position times, the
uncertainty of the
momentum, which is more or less the
velocity is always bigger
or equal to this constant.
This is simply a no.
This tells us something about nature,
and this is really interesting.
This is an intrinsic uncertainty
which lies in nature.
So this is not because
our microscopes are too bad
or we are not looking close enough.
Where the electron is are not fast
enough. This is an intrinsic
uncertainty when it comes to small
particles.
This is how nature is
is behaving.
And this is really
contri or you
would not expect that.
I would say
now with this simple
principle, we already can explain
tunneling, quantum tunneling, the thing
that we talked about already,
the electron coming close to a to
a barrier to an energy barrier or
let's say it's a wall.
And usually you would expect that a
particle cannot go
through the barrier.
But in fact, now you see this diagram
that that we physicists love
and now you see the probability
says it's very probable that
the electron is on the left side
of the barrier.
But there are still still a small
probability that the electron is
actually on the other side.
And this is the reason why a tunneling
really happens and can be measured
just because there is a mathematical
probability that the particle is
on the right side.
It really appears on the right side every
once in a while.
And this is what I already showed you
with this beautiful, beautiful
animation and simulation by
Jean-Christophe Arm.
Yeah, this is physicist Humar
told you a Heisenberg.
This is actually a toilet in my faculty.
This is what physicists laugh about.
But anyway,
OK, we talked about uncertainty,
uncertainty in position and velocities.
But this is not only true for
positions and velocities, but also for
quantum states.
What I mean with that, let's
talk about information, so a classical
bit, you all know, can be turned on, turn
off or in binary code it can
be one or zero
with quantum bits.
It's a little bit different.
And we already talked about uncertainty.
And the same is true here for quantum
bits. If we talk about states of quantum
bits, you see here
the the the quantum
bits, the cubitt can also be one or
zero, but it can be everything
in between.
That's what physicists call a
superposition.
These super positions are really
excuse my language, Fickell, because
they only you
only have a superposition when
when you don't look at at the cubitt.
So you don't you
are not allowed to make any measurements.
As soon as you make a measurement,
you end up with a with a clear
one or zero as a state
for the covid.
But as long as you don't look inside
the box, no information in, no
information out, then you have
the superposition this
any state in between and you
can actually work with this
superposition.
So is that the same?
As when I would take a coin
flip, that coin captured it in front
of 400 people and keep my
hands cover covering up to
the coin, is that a superposition?
No, it is not.
This this the state
of my coin is described by
you basically probability it's
50 50. Either it is heads
or either or it's tails.
And of course, my ignorance, because I
haven't looked yet, but the fate of
the coin is already chosen.
That's quite philosophical,
OK? The fate is chosen.
If I uncover it, I see the result.
But the result was there before.
This is not true for superposition of
cubits.
As long as we haven't looked at
the fate of the cube, it wasn't
decided yet.
There is no records there.
There is no decision made yet.
And this is what made makes cubits
more powerful than
all. That's one reason why it why there
is power in the concept of quantum
mechanics.
Now, let's talk about we already
talked about cubits, but the question
you could ask now is, of course, what is
a cubit? So, I mean, in real life, where
where can I see one?
We start again with a classical
comparison, one and zero.
We could take this this spinning tops
as a as as yet another
picture is.
Either it is facing down and
turning anticlockwise
or it is facing up and it's
turning clockwise.
The same is true.
Actually, it is not true for cubits.
Cubits are small particles
and small particles
like electrons,
protons, photons.
They have a property
that physicists call the
quantum spin.
You should not mix this
spin with a quantum spin.
So actually the electron is not turning
and spinning, but still
it's a nice picture. So we use it.
But what you really can measure and see
is that qubits have a small
magnetic field,
so they have a North Pole and a South
Pole.
And that's pretty that that
comes handy because we now can
manipulate the state of the of the
cubit if we take a rather
strong magnetic field and
we bring in our our
cubitt, it will very
likely align
in the position of the lowest energy.
That means, of course, the North Pole of
the of the magnets will face to the south
and the South Pole of our little Cubitt
magnet will face to the north
just like a compass needle.
Of course, it can open the compass
and invest a little bit of energy and
turn the compass needle in the other
direction. The same you can do here.
You can invest a little bit of energy
and turn the needle the other way around.
This is other state.
It's a higher energy state and we
also use that in our
cubitt so you can
produce one and zero positions
of your cubitt. And we come back to that
later when I show you how we actually do
this.
So then we are at a point where we need
to information.
So how probable is it that we find
our Cubitt in a
up facing position and how probable
is it that it will face down?
So two numbers and we can describe
our cubitt.
That's not very exciting,
I would say, but it gets
exciting when we start looking at
more than one Cubitt, because
then is something
very interesting happening.
Let's start first again with two two bit
systems, both spins
or this year, both down, one down,
up, up, down, up, up.
And of course, you know, one one two
two zero zero.
So although the system, our two
classical bits system can have four
states, we need to information
to wholly describe the
system. You need to information.
What is the state of the first bit?
What is the state of the second bit?
That's gets a little bit more complicated
when we come to Kupets and I spare
you the and
even more, I spare me the mathematics
behind it to Cubitt
system.
It can be easy.
Let's say this this case here, both
cubists facing up very easy to
qubits facing down very easy.
But this year isn't easy, isn't
easy at all.
This is what physicists call entanglement
in that state.
The one cubit is facing up, the other one
is facing down and the two Cubitt
system that entangled Cubitt system is
perfectly free in whatever direction
it wants to face.
We were already talking about that when
when I introduced the superposition.
But the same is here, the entanglement.
Now we have two cubits and they can face
in whatever direction they want.
So they are more or less perfectly free.
With one exception.
The one cubit is facing the one
way, the other one is facing the other
way. So you see, you need more
information to describe such a system.
In fact, for a two cubitt system,
you need for information.
So a D
and this entanglement states
B and C, which comes
out of rather complicated
mathematical calculations
for inflammations
for two cubits.
But it's getting more extreme if we are
talking about more than one or
two bits versus
two cubits.
You see here the classical bit system.
Of course, you already
already know 10
normal classical bits.
You need 10 information and information,
four and bits, but four cubits.
It's two to the power of an information.
So this system is
getting rather complicated
fast.
In fact, if we would succeed
in having 300
perfectly entangled cubits,
this number here, two to the power of
300, is so big that you
need more information than we
have.
Then we have particles in the known
universe to describe this system.
So you see the system
is getting getting complicated, but
of course, you can formulated the other
way around.
We have a complicated system so we can
work on complicated problems.
And I touched back on that,
I guess, on the next slide.
But first, I have to show you one more
thing concerning the strange nature
of cubits.
Again, we started with the register,
if you want to do calculations or if you
want to rewrite the information in such
a register, you need.
You need steps,
process steps, so that takes time, so
calculation's rewriting of the
register
positions here takes takes your time
in entangles
systems and cubitt superposition
or entangles to Cubitt
systems.
This looks a little bit different than I
have already told you about that
I told you about this entanglement that
we have this to entangled cubits
and that they are not independent of each
other. So if the one is facing
the one direction, the other one is
facing the other direction.
And that has a consequence
in so far that if you
manipulate one of those cubits,
you manipulate
all of them immediately.
And that's, of course,
there lies a real power because
you you can in parallel to
operations that you couldn't do in a
classical computer.
Are our quantum computers
faster for every
problem, for all the problems?
Well, no, they are not.
In fact, for most of the problems,
there are actually slower.
If you would sit on your couch
and stream a movie,
the quantum computer wouldn't have any
advantage.
There are specific problems where
quantum computers have
the edge over classical computers, and
that's problems that
you are, of course, familiar with.
For example, the public key encryption
protocol, which basically is
based on the fact that it's very, very
easy to take to integer
numbers, prime numbers
and multiply them.
And everybody of you could do that
within a minute, I guess, and tell me
that the result is this large number
here. It is more complicated
to do it the other way around.
If I would ask you, what are the prime
numbers that, if multiplied, give this
number?
This is incredibly
hard and so hard that that classical
computers needs thousands of years
to do that and a quantum computer
would only need some minutes
to do that.
The reason is that this that
a lot of calculations can be
or can be processed in parallel
in another or other non
reciprocal problems are also
problems that seems to be very suitable
for quantum computers.
For example, this year, the phone book
problem. It is very easy for you
if I ask you for the telephone, I give
you a telephone book and ask you for the
number of John Doe.
You could easily tell me the number.
If I just give you a number
and you are supposed to find me the name
from this phone book, that
will be rather hard.
And this, again, is a problem
that can be solved with quantum computers
more effectively.
In fact, I told you,
I'm not very strong in quantum
algorithms, but I show you at least
the more famous
algorithms that were found.
And they were actually found quite some
years ago, 1994 and 1996,
the shore over a rhythm's algorithm,
which is for intentional factorization.
I talked about you see here, if
we take a typical example,
then you see that classical computer
would need 10 to the power of 19
steps, while the quantum computer only
needs around 90 steps.
And the same for the phone book,
60 million entries.
The only strategy basically that
that a classical computer
have is starting at a and go through
till he finds the number.
No, it's not starting with a but we
started with a telephone number, but he's
starting with the first entry and go
through the entries.
And at
one time he by chance finds
the right name to the number and the
quantum computer is faster there
with a lot of less steps to
find the right name
to to a number.
So I told you,
I'm not strong here.
But the message I want to send with this
with this picture is this year the bottom
line, we have the algorithm.
So we need hardware now.
So give us the hardware and
we are taking.
If we are OK, if we are taking
it or talking about the realization
of a quantum computer, it was a nice
paper from a from a guy in
from the University
of Chancel,
he established a de Vincenzo
criteria for quantum computers.
So you said if you want to realize
quantum computers, we need to realize
or address these problems in
four quantum computers.
And they are pretty obvious.
We need well-defined cubits.
Of course, we need qubits that are
that we can track, that we keep in place.
And the next thing
is we need to initialize them, that we
need to give them a pure state, either
superposition or tell them B one
or B zero.
We need quantum gates, of course, to do
operations algorithms.
We need measurements to read out
our kupets whether or not they are
one or zero at the end of our
calculation.
And we need long coherence times
that need that means.
I told you already our super positions,
our qubits, their fickle and
they don't they they act
strange and randomly at times.
So we need qubits that are rather
stable.
OK, we need to address all of this
in in the next slides.
But let's start with the shortest
overview of quantum computing here.
2001, IBM
showed the first real quantum
computer and our computer
nuclear magnetic resonance computer,
and they actually had a short algorithm
running on it.
They're the.
So that they they used to shore up
a rhythm to do this factorization problem
I showed you, and the
incredible number they were able to
process was find the
prime numbers of this number.
Is anybody capable of doing that here?
All right, the gentleman said not not
at this time, but usually I would say
you you are as good
as a quantum computer when it's not
that early on a
on a Congress day.
OK, it's I give you the result.
It's three and five.
Oh, man,
I felt with my heavy metal band and now
I prepared a good looking
presentation and all I need to do to
impress you is giving you the prime
numbers.
And I have I really
have to rethink my my life after
this Congress.
OK, that was 2001,
2005, 2011.
Incremental
improvements of the quantum computers,
2011 hyphy China,
four cubits giving you the number of
the prime numbers of this number.
And these are other implementations
of quantum computers, as you know.
I will talk now about diamonds
and quantum computers with diamonds.
But if you're interested in these
implementations, I strongly suggest
if you haven't seen it, the
wonderful presentation, Let's Build a
Quantum Computer by Andreas Davies on
this at this Congress.
Rewash it if you haven't seen it, because
it was really
fascinating to see those concepts.
I'm
the problem.
Oh, I missed my joke.
You don't have.
OK, what I wanted to say is,
although Andreas realized a
quantum computer here with these methods,
they have some kind of drawback.
All these implementations are rather
complicated.
You need large lasers.
You need vacuum chambers.
You need strong electromagnetic fields
to trap your cubits.
So this is nothing that
that you would put on your office desk.
So this is what I call
and police act surprised.
But as physics.
So, of course, physicists were looking
for four alternatives
and they were pretty surprised to find
an alternative here
in diamonds, actually diamonds
have extremely stable
cubits
at room temperature.
You don't even need to cool down your
devices.
So this is something where scientists are
really looking at and hoping for
for improvement in the field
of quantum computers because the diamond
has such an incredible, such incredible
properties.
And I will tell you now why
they are so incredible.
But actually, we don't.
What we need is not we we don't need
perfect diamonds, but we need
diamonds with small defects.
And I like this this quote
here from Colin Humphreys, a physicist.
Crystals are like people.
It's the defects in them which tend to
make them interesting like that very
much because we don't need
perfect diamonds.
We need diamonds with specific
defects in them.
This is a diamond.
Lettice Diamond is made out of carbon.
And what you see here is
the special effect. I'm talking about the
N.V. Center and the M stands
for nitrogen and the V stands
for vacancy or void.
So a missing carbon atom.
So that's what what you see here.
There's the nitrogen atom
and there is the the void,
the missing, the vacancy, the
missing carbon atom.
And this this structure
in a diamond. The N.V.
Center has remarkable properties.
They are a very excellent trap for
electrons. And we already talked about
that, that electrons have a quantum spin.
So we have a trap for electrons.
The electron stays at that position
and it's rather stable
for some reasons in
those qubits have a long coherence time
at room temperature and diamond
question now, of course, is,
oh, let's start with this here.
We succeeded with the first point.
We have well-defined qubits.
Now, the question, of course, is can we
measure them? Can we initialize them?
So first measuring them, can
we measure the state first and easy
picture what physicists
do when they want to measure something is
they use lasers. So we shine a laser
on this and these centers and we get
a signal back. And the signal is a little
bit different to that, that we
shine in so we can distinguish
between the laser that we put in and
the light that comes out.
Now, we make that a little bit more.
OK, that's a picture of
such a measurement.
What you see here, it is tiny.
This tiny points are actually
single and V centers in our diamond
crystals.
So how does that
work? I want to explain to you that a
little bit
in more detail.
This is
these are energy levels in our diamond.
We started with the ground state.
The electron is at the ground state.
If we now should, with our laser light
on it, the electron
will take some of the energy and jump
up to the excited state.
It won't stay there for long.
It stays there for some milliseconds and
jumps down then back again.
And what we see then here is fluorescence
light, light that we can measure
and we get information from that.
Now we play the same game
again, but we change the game a little
bit and
we change it in the beginning.
Let's start again with the electron on
the energy ground level,
and we use some microwave pulses
to give the electron a little bit of
energy. And what happens then is the
electron changes
its spin.
You remember the picture I gave you, the
the compass needle, the little magnets
in a magnetic field.
If we invest some of the
microwave pulses, a little bit of energy
and we turn and spin the cubitt
in an up position.
So now we can, with this microwave
pulses,
initialize the cubitt, whether
it should be zero or one.
And now we repeat the experiment
from the left side and something
impressive happens.
Now, again, energy, the electrons jumps
up.
But because we are coming now from
a from a spin up state,
something different happens.
It doesn't jump back down again and
giving us the fluorescence light, but now
it jumps to an intermediate
state, stays there
for a few milliseconds and then jumps
back down to the ground level.
And the surprising thing about that is
we don't see light or I
should say we don't see the fluorescent
light we are looking for.
So you see.
Now we can initialize
the state, we can
measure the state with our laser pulse
when we see light, we know the electron
came from the ground state.
If we don't see any light, the electron
came from the spin up state.
And what we also can do is if we
choose the microwave path, right,
we can have a superposition.
So coming back to the to the eventual
Vincenzo criteria, we
have well-defined qubits in our Diament
we have we are able to initialize
to a pure state.
We have cubitt specific
measurements. That is our laser.
So what we now need
are Quantum Gate.
So we need to calculate or
do operations with a quantum computers.
I show you an example, not for diamond,
for another spin system,
because that's a little bit easier to
explain on one slide.
But more or less, I guess
you you get the idea of how we
are doing that with Quantum with
Quantum Gate. So
I show you the control not to see.
Not great for the few of us
who don't know what that is,
we have a control bit.
This is the red one and we have a target.
But the blue one, if the
control bit is zero, nothing will
happen to the target because if we
have if the control bit is one,
the state of the target, it will
be changed.
So if we start with the zero zero, we
end up with a zero zero zero one,
ends up with zero one one
zero changes to one one and
one one changes to one zero.
So how do we realize
I mean, in a classical computer, you
realize something like like gaits
transistors.
How is that realized?
And a quantum computer?
Well, I show
you this with
an example with a model system of two
coupled spins, an electron and
the proton.
And as you might know,
this is a hydrogen atom.
So we are doing our calculations with
a hydrogen atom.
Again, we are talking energy
levels here. So we are starting with
the lowest energy level would be
the electron is down, the proton
is down, lowest energy level
corresponds to zero zero state
electron down, proton up
zero one electron up,
proton down one
zero and both spins up one
one state.
You already heard
how we choose the spin of the electron
electron transmission electron spins spin
resonance.
That was simply the story.
That was simply the microwave pulse
that we are inducing and by
that choosing the spin of the of the
of the electron.
So now we can determine whether or
not we have electrons spin up and
electrons spin down.
And now we do something that that is
called nuclear resonance and
are again electromagnetic
pulse, but a different energy
and frequency.
And what we do here now is we choose
wisely that the pulse has
this energy here and then
we have exactly the not transition,
because only if the
electron is spin up, we
will have a transition between those two
states.
So it is pretty
in your face, actually.
OK, the idea of doing
operations with a single atom, it might
be not really be in your face, but
you see that how you actually
do it. This is rather simple.
You need one single pulse
to do such a rather complicated,
logical gates
or realize such a complicated gait.
Of course, I have to say,
you just need a single pulse if you have
a good spin system.
That's, of course, what you need for
something like this.
OK.
In principle, I have shown you that
what that we can have well-defined
cubits that we initialize
to a pure state how quantum
gates could work in such a system
and how we do cubitt specific
measurements.
But now I have started or
the title of my presentation says
that I'm working with Diamond and we are
trying to realize quantum computers
in Diamond. So your question
should be where is this guy getting
his diamonds from?
Are we mining them?
Can we get them out of a mine?
This is an old mine,
an old diamond mine in the
Kimberley, South Africa.
I like this picture very much.
And it is
this mine is long closed like I
think 1914 or something.
But this is believed to be the
the largest hole that was
by bare hands. So the people were
actually getting the rubbish out
there with their bare hands.
So this is the biggest hole.
Could we take diamonds from diamond
mines?
No, because I have
already told you that we need
very specific diamonds.
We need them first to be very clear,
very perfect.
And then we induce very specific
defects, the envy centers that we already
talked about.
So if we cannot find them in nature,
of course we make them by ourselves.
So what we use there is a
microwave plasma
chamber.
Funnily, it's not so different
compared to the to the microwave
ovens you have at home.
It has the same frequency.
It has the same power.
The only difference is that we
we focus the microwaves
very precisely in the middle of
our vacuum chamber.
And by that we can ignite a plasma
in the microwave
plasma chamber.
And the plasma is actually that is
what you see glowing here.
Why can we make diamonds from a plasma?
Well, we use very specific gases.
We use methane
as a carbon carrier for
you see here the carbon atom and four
hydrogen atoms.
And we use hydrogen because we
need that for the chemistry.
And what happens then here in the plasma
ball is that we break those molecules
and we have then
the three reticle and then
we we do something tricky.
We we offer those ridiculous
diamond surface.
We call that the diamond seed crystals.
We bring it close to the plasma.
And then more or less like Lego playing
by self organization, the
this radical goes to the position
on the diamond and continues to
grow the letters of the
of the diamond so we can start with a
rather dirty one and start
growing our perfect crystals on
top of it.
So that's that really work.
I want to convince you that that works
because this is a video
of our plasma chamber.
You see this greenish plasma
over the crystals here.
And these are our dirty crystals.
They ever heights of
around half a millimeter and the diameter
of around 10 millimeters.
So they're a rather big and
OK quantum computer application.
We don't need really thick diamonds.
But of course, if you have a lab
and you have a plasma chamber in there
and you have seed crystals,
the first thing you do on a weekend where
you don't have any other plants, you grow
large diamonds.
So.
That's nice that you clap your hands
because I'm doing that from your tax
money.
Thank you.
OK, this is a movie.
Let's see how these diamonds are growing.
This is unfortunately, this is in the
course of three days,
a Friday evening till
Monday evening.
Those diamonds don't look very nicely
made.
Now they are three millimeters tall.
So they're not.
No, they're really
rather large sized diamonds,
perfectly single crystals in the middle
and not so perfect and not
good looking in the in
the outer edge here.
So what I did is I took a
laser and cut out the perfect diamonds
diamond and went to a jewelry shop
and asked them because
they really don't look like you could
impress anybody with them.
But I went to them and asked them if they
can polish me the diamond
like a real brilliant like
the stones you would have in rings or
amulets or something.
So the man there was
suspicious because I had never seen
such a stone.
So he asked me what
material that is.
And I said, that's diamond.
And then he said, where
do you have it from?
And I said, I made it by myself.
We had issues, I would say,
but I found somebody who was able to
polish me, the Stones, and they look like
this, they really look beautiful.
And whenever I want
to impress the crowd like you, I have a
diamond self-made diamond in my trousers.
So if
you want to take a look after the
presentation, just come up to me and
take a look. This is not really a perfect
diamond, but it's enough to
impress people,
right?
OK, we have perfect diamond snow.
But the problem is and we're coming
to the end of my presentation.
The problem is we don't want perfect
diamonds.
I told you, we want and we centers in
the diamond. So how are we getting
now the envy centers?
Precisely in our perfect diamond
crystals?
Well, we take our
iron guns.
Something else that I buy from your
tax money.
We take iron guns, we take the perfect
crystal, we take iron guns and we shoot
irons, nitrogen irons, obviously
on our crystals.
And what happens then is first a
pretty mess. So the nitrogen
is in the crystal and then we we
do something that we call annealing.
We put the crystals at 700
degrees and some kind of Auvergne
and then
something happens.
The nitrogen brings mechanical
stress in the crystals and the stress
or the crystal wants to relax
the stress.
So what happens automatically,
actually, is that that the V centers
the vacances move to the
to the nitrogen without us doing anything
very professional with it.
So that is one way how we can produce
the N.V. centers in our crystal.
The other one, the other method is called
Delta Doping.
I already showed you how we grow the
diamond layer by layer and that
is shown here at one specific
time. We bring in nitrogen into
the process and then of course we deposit
the nitrogen into our lettuce.
Now we have the nitrogen, but no
vacancies. Now we take an electron
gun. Yet another thing I
buy from your tax money, we shoot in
vacances here, do again the annealing
step and we end up with envy
centers.
Yeah, so
now I'm really coming to the end.
Well, we have where I showed
you that we have well-defined cubits, we
have we could we can initialize them,
I already showed
you that. So we are able
in principle, to produce
a diamond quantum computer.
How far are we with that?
What is the state of the art?
Well, it's in its infancy,
of course. So
there was a two bit cubits.
Quantum Computer realized
Grovers algorithm was running on it
in 95, OK?
And the calculation was pretty pretty
right on the first try.
If we really would want to
decode
our courts in a in a
reasonable time, we need at least
our I read an
estimation that we need four thousand
cubits to to do that
and four thousand.
Perfect, the entangled cubits is really
not easy,
but still people are working on that
based on Edward Snowden's
documents, you see that the NSA
runs a project
worth 80 million
called penetrating hard targets, like
the name of it, very much to
develop quantum computers.
So I already
told you that I like
the presentation.
That's really my last sentence.
Now, the presentation of Andreas
yesterday.
And there was
one remark that I want to repeat because
I liked it so much, if you ask
me.
Quantum computers are not there right
now. They are not effectively
working, but they will come
because the technology already is there.
It is very likely that those concepts,
because you see there, there are rather
complicated.
The knowledge about the quantum computers
will be in the hands of governments
or rich companies.
So it's very important that we
keep an eye on the developments and
what's possible and what's
not possible and
to end on the positive side.
I will keep an eye on that for you
with your tax money.
So.
Before we start with a question and
answer, I have a podcast, if you like,
the way I talk about science, the podcast
is called Mythologizing, Correct?
I do it with my Ph.D.
students, who suffers very much
under me. So
give him some love by downloading
our podcast. Thanks.
Nice plug
the.
Oh, yeah, it is nice plug.
OK, so we have time for some Q&A.
There's four mikes in this room too.
There to now also
Basti ISC, of course.
And we also if you're unable to get up
for like an actual medical reason,
we have a backup.
So all your angel to give you a mic.
So we'll just start with number two.
OK, so thanks for the talk.
My question is, can you realize
entanglement between different N.V.
centers, which I believe would be
necessary to do more than two, but
quantum computing?
Yeah, first,
before I answer the question, you're the
first
audience who's not asking about the
diamonds and whether or not I'm rich
because I'm producing permanently
diamonds. But I appreciate that.
Well, yes, there
were realizations of
entanglement of two cubits
in diamonds and more than two cubits and
diamonds.
But what you're talking
about is exactly the problem that we are
having and what we are doing
research right now on, because
the there are a lot of parameters
that influence the stability
of those cubits.
In a quantum diamond computer,
for example, the distance between the
cubits is a very important factor.
The distance of the cubits to the
surface of the diamond is a very
important factor.
The the
the chemistry that is that is
on top of the diamond
crystal even makes a difference.
So that's
actually the problem we are working on.
Thanks.
Does the Internet have a question?
Now, Internet still.
Yes, the Internet has a lot of questions,
um, at first I have to
apologize for being imprecise.
You spoke about the
Cupitt specific measurement, part
of the talk, the question
is what happens
with energy if
the Cubitt does not
drop to the to the
lowest level?
I think you mean when when we're starting
with the with the cubitt up.
And yeah,
I was pretending that there is no
energy emitted, but that's of course not
true. The energy has to go somewhere, but
it is in a different frequency.
So if we are just measuring the
fluorescent light or we're just looking
at the fluid since light we want to see,
then
we don't in that frequency
we don't see a light.
But of course, the energy is going
somewhere else so that that will be light
be transmitted, but in another frequency.
So you don't see it?
We don't see it.
And does this effect happen
multiple times?
Yes, of course. Yeah, yeah.
You can initialize your system again
and start the process
over again. And that's actually what's
what's being done.
You you repeatedly initialize your
system, measure it and do that
thousands and millions of times
again and again. Yes.
And the Internet is also
interested if it happens.
Um.
If it happens from alone
or.
Dusty, decoupage drop
by and not being measured.
Yes, the cubitt would also drop without
being measured.
That's one again, one and one
problem that we need to realize.
We want to have stable
cubits that that keep their position
as long as possible.
But every once in a
while, of course, the cubitt will change
by chance.
So this is exactly what you need to
control. You need to have stable systems
that stay in the position that you want
them to be for as long as possible.
So but you're absolutely right.
And that makes it hard at
this time to realize quantum computers,
to have them stable over the time.
Yes.
OK, thank you. And just a quick reminder,
if you're leaving now, please
be aware that there's a camera right
there. So if you stand up in front of the
camera, nobody's happy.
So.
OK, microphone number one, please.
Well, first of all, thanks for spending
our tax money and a really reasonable and
totally cool way.
So I was wondering if
we assume agencies with basically
unlimited funding and highly
compartmentalized information.
Do you see any practical risk that
they, in air quotes have the technology
at scale and we simply do not know about
it?
Yeah, I'm asked this question.
I'm asking quite a lot.
And of course, it's hard for me to
to to really give an estimation
about that.
Usually I would say I'm I'm pretty.
I have an eye on the on the on the
developments that that happen in
in in science or in my
field at least. And what you usually
see is that you you
have publications on one topic
and when it's really getting dangerous,
those publications will drop and you will
not hear any more
about the findings in that field.
And people, the experts that are working
on in these fields are
vanishing.
So I would say
optimistically, I don't think that they
are much further, but I cannot say maybe
they are further than the publications
such with with Stuxnet.
We've seen that academia
has said some people have said that
what was in Stuxnet cryptographically
was years or even decades
ahead of what academia knew about.
So,
yeah, what that makes
me a little pessimistic view on the work
I'm doing every day.
But, yeah, I
hope you're not right, but I cannot.
Yeah.
Thank you. Thank you.
So if there's no talk by Nicholas next
year, you know what happened.
I'm either really rich
then or turn to the dark
side, so,
yeah, right.
The chances are really low,
Mike.
Number three, please.
Hello. Um, do you think there's
a big difference between building a
quantum computer with a few hundred bytes
or a few thousand bytes?
Because that's an important question,
whether we should elliptic curves.
And do you have any estimation
how long it will take until we have a
practical quantum computer?
That's really tough questions because
we are this is really fundamental
science right now.
And we are really struggling with a few
cubits, having them entangled
for a longer period of time or
for a time. That's enough to do
calculations with that.
And you see, we are like, uh,
yeah, this this is really not like
Moore's Law that we could say now we're
at ten.
And so we just calculate and say in 20
years we have the thousands that you
need.
There might be there is so much
fundamental physics to be done there.
Material science.
I couldn't even tell you if a real
working diamond or a quantum computer,
there will be quantum computers, that's
for sure. But will that be realized
in diamonds? I cannot tell you because
there are so many problems.
Just what you said.
If you if you were starting with a few
quantum bits, they they disturb
themselves. And so it's getting
increasingly difficult if you increase
starting with four cubits going to eight
or 16.
So that's really hard.
I don't dare to give you any numbers
if that would be possible
in the future or even when it
will be possible. So I'm sorry.
Can you say something like this is much
more difficult to build 4000
compared to four hundred bits.
That's really important for the
cryptographic implications.
Since we haven't realized for hundreds,
I'm not sure we find methods
that will scale.
That's that's the question.
If we find methods to produce, I mean, we
are really struggling to bring in
precisely of four
or eight in a specific distance
from each other. So, yes, when
when we have the methods to make it with
aid, maybe it's possible to make it with
four hundred and then we are at four
thousand.
But I see
no technology now that is scalable
to do that. So right now
I don't know how.
Thank you, Mike.
No one, please, you really
often talked about the
the the state of the
economy in the diamond.
How long of a
time period you're talking about?
They they stay stable
some milliseconds.
So I think from the
one publication that I showed, they
stated something like two milliseconds.
But that's enough to do some calculations
that that will be enough.
And then again, like the question before
we can initialize them again and do the
calculation again.
But that's, again, something
that we are working on. This is to
improve that time to make more
calculations after the initialization.
How about the Internet?
Yes, one question is,
or you talked a lot about our tax
money to your population excess.
Yes, I, I try to yeah.
My last paper, not on diamonds, but on
graphene was published op mixes.
So I'm I
is I really suffer
from the publication
system.
I feel your pain.
So I think it's really.
It's a shame that that's
you are not able to access the
publications.
The funny thing is not even I am able
to access all of my publications that
I published
some years ago because we canceled
the subscription of the Journal.
So I cannot access my own papers.
And that's absolutely bullshit.
So the whole system is
fucked up, but.
But to be fair, the
European Union is changing the system a
little bit now when I'm funded by
European money and also German
money from some funding agency,
they they expect that
that's a sign that I do will
be published open access.
So there is something going
on in that field. So that's not so
pessimistic or it's getting better there
at least.
Mike, number two, please.
You said you watched kind of watch
the market for us.
And I've got a question about
Dave.
Do they have a quantum computer
that conforms to your criteria
or I mean, Dave is a company
and so they are not publishing what they
have.
So it's really a little bit difficult to
get real hard facts on that.
But as
as from from everything
I know or I see
they have a different
realization of the of the quantum
computer.
They have something that is called
adiabatic quantum computer.
The real difference there is that they
are not working with,
as far as I understand it, with
really entangled covid.
So they are not
they haven't realized the
the power or they haven't set free the
power of a real quantum computer.
As I said, it's really hard to get
information out there.
But from everything I have read,
this is not a pure quantum computer
that I have suggested today here.
But this is, of course,
something.
I mean, this is a big company.
There are big companies behind that and
there is money and they are at least
working on the realization of the
of the principle.
So this is what I wanted to say with
the last sentence. So we need to be
aware of that, that people are working on
that people with lots
of money. So they are not
there yet. This is not a quantum computer
I'm talking about in the quantum computer
that will crack all our
passwords.
But people are working on that.
Number three, please,
you presented two different
methods, how you get the nitrogen and the
gaps and the diamonds and the well
and the pictures, we saw different
orientations of the nitrogen and
the gas.
And I was wondering if it makes a
difference and if so, if you can
influence what is then orientation.
It makes no difference.
And we we don't have
influence like like you saw.
It's more like a random process.
So we we shoot the ions in there or
incorporate the nitrogen and then make
this tempering step.
And this is a self organizing process.
This is actually the
this is the heart thing or we
were working on that. So I'm
funded by this Mercato Research
funding agency. And that is the
the task that we are working on right
now is how how are we
able to put the N.V.
centers at a specific positions where we
want to have them.
But that is not orientation but position.
And how can we.
Yeah, how is that influencing the
performance of the envy's centers in our
diamond?
But in the end, there is not
when it comes to the orientation or this
annealing step, there is no control if
you want like this. I mean, we have some
process control of of course, temperature
and and basically
temperature to
to make this more efficiently or
lets a vacancy move faster and and
give them more energy to move.
But that's all.
Yeah.
Thank you. OK, we are unfortunately
out of time, so I have to officially shut
this down. But here Nicholas is still
here. So if you have questions, just come
up. Thank you.
Police used to from Texas.