- Can you picture the
world without computers?
This is a scenario very hard to imagine.
Yet even the most powerful computers
will take up to thousands of years
to perform more complex tasks,
such as breaking an encryption key,
or simulating chemical reactions,
or modeling financial data.
So scientists are betting
that quantum computers
will be able to solve these problems,
that will lead to more secure encryptions,
or the discovery of novel
materials, new medicines,
or even the prediction of market trends.
There is a small detail.
Well, actually, not so small.
Quantum computers obey the
laws of quantum mechanics
and these laws are completely different
from the ones of the classical
world we live and know.
For this reason we need to
re-engineer the hardware,
rethink the software, and
reinvent communication protocols
to interconnect these quantum computers.
The first ingredient we need
is a quantum bit, or a qubit.
In contrast to a classical bit
that can only take a value of zero or one,
a qubit can take an infinite
possible combinations
of zero and one at the same time.
This is a crucial property of qubits
that makes quantum computation
so powerful and attractive.
A promising candidate to use as a qubit,
it is light in its
minimum value, a photon.
Photons are great qubits
because they can travel long distances
and they weakly interact,
but it is really, really hard
to isolate just one photon,
and this is what I'm trying
to achieve in my research.
I invite you to take a look into my lab.
This is how a developing piece of hardware
for a quantum computer,
or quantum communication
system, looks like,
and just like the very first computers
it takes the entire room.
But the core of the apparatus
lies in a metallic chamber
that only contains rubidium atoms.
Using powerful lasers and electromagnets,
we collect and cool these atoms
to temperatures lower than outer space.
By shining a very, very weak laser light
and manipulating the atomic interactions,
we can make photons from this laser
bond with each other like molecules,
or we can make them repel each other,
so one photon comes after another.
This is remarkable, because
by using atomic interactions
we can change the photons own nature,
and make them interact in different ways.
This means we are able
to isolate single photons
to use them as qubits, to
perform a quantum gate,
the basic logic unit
for a quantum computer,
or we can send and store
quantum information
from one place to another.
My experiment adds one more step
towards making quantum
technologies possible.
