Australian Institute of Physics

South Australian Branch


at 7:30 pm, Tuesday December 9th 1997

in the FLENTJE Lecture Theatre

Plaza Building, The University of Adelaide

(go down the steps at the NorthEast corner of Hughes Plaza,

or enter from the Horace Lamb building)

"Trapped Ions, Schroedinger's Cat, and Quantum Computation"

by Dr David Wineland

NIST, Boulder

With the current interest in quantum computation, several

ideas for practical implementation of quantum logic operations are

being investigated. One possible scheme uses trapped atomic ions as

"qubits". Qubits can be "wired" to make logic gates; this can be

accomplished by coupling the ions' internal states through their

(shared) motional degrees of freedom. A fundamental quantum logic

gate has been realized along these lines at NIST. Scaling of this

system to a size useful for computation will need to overcome the

effects of decoherence; this issue is closely related to the

survival of "Schroedinger's cat", a bizarre situation which follows

from the rules of quantum mechanics where a cat can be

simultaneously both dead and alive.


David Wineland studied at University of California, Davis and

Berkeley, before gaining his M.A. and PhD from Harvard University

under Norman Ramsey in 1970. He has worked at the University of

Washington and the National Institute of Standards and Technology

(formerly National Bureau of Standards) in Boulder, Colorado. He is

presently Project leader for the Ion Storage Group at NIST, and has

been an NIST Fellow and affiliate faculty member at Colorado State

University. He has been distinguished with numerous awards,

including the 1990 Davisson-Germer Prize (APS), 1990 William F.

Meggers Award (OSA) and most recently, the 1996 Einstein medal for

laser science from the Society of Optical & Quantum Electronics.