You may think making a three-point turn in your car is easy, but how about doing
the same with a single-charged atom?
That's what scientists have achieved for the first time, marking a major breakthrough
for physics and a first step towards creating the complicated labyrinth of 'atomic
motorways' needed for a quantum computer.
The microscopic motoring manoeuvre was performed by University of Sussex physicist
Dr Winfried Hensinger with colleagues at the University of Michigan, USA. Details
of the experiment are published in the January 2006 issue of the journal Applied
The ability to shuttle ions (charged atoms) in a controlled environment is seen
as an important demonstration of how to harness the seemingly magical properties
of atoms. This development will help scientists to store and analyse the vast
quantities of data used in highly sophisticated calculations - in super-fast
To be able to build this kind of computer, scientists need to trap ions - no
mean feat in itself - then control their movements in a sophisticated labyrinth
of 'atomic roads'. Such a process has previously been carried out for single
ions along one line, but Dr Hensinger (now Lecturer in Atomic Molecular and Optical
Physics at Sussex), and the Michigan team have shown how they can make atoms
turn a corner.
Keen for more driving pleasure, they even managed to switch two ions around by
having them perform a three-point turn. This will hopefully allow eventually
for the mass-manipulation of atoms, vital for the operation of a quantum computer.
Ion traps are made from micro-fabricated electrodes, in which ions are controlled
by electric fields in an ultra-high vacuum chamber. The new construction, the
first two-dimensional ion trap array, is the most sophisticated yet. The ions
are steered inside a T-junction that is laser micro-machined in thin layers of
a material called alumina.
Dr Hensinger says: "This is big news because it is very difficult to trap atoms,
let alone manipulate them in transit. This and other recent developments show
that it should be possible to build a quantum computer with trapped ions. Now
we can take two atoms and swap them around, which mathematically corresponds
to a fundamental requirement for a quantum computer. This is the prerequisite
to go from something academically interesting to something useful. This is
a quantum leap in the development of the quantum computer."
Quantum technology could be used in the future to understand chemical reactions,
create medicines, ultra-fast communications systems and seemingly impossible
simulations, such as the creation of our universe.
Notes : Dr Hensinger heads the Ion Quantum Technology
Group in the Department of Physics and Astronomy
at the University of Sussex. The group has close
links with the Trapped Ion Quantum Computing Group
of Professor Christopher Monroe at the University
of Michigan, USA. For details see: http://www.sussex.ac.uk/physics/iqt/
For further information, please contact:
Sussex, University of
+44 (0) 1273 678209