Quantum Information Processing, Vol. 3, Nos. 1–5, October 2004 (© 2004)
Quantum Information Processing with Trapped Neutral
P. S. Jessen,
I. H. Deutsch,
and R. Stock
Received February 3, 2004; accepted March 31, 2004
Quantum information can be processed using large ensembles of ultracold and
trapped neutral atoms, building naturally on the techniques developed for
high-precision spectroscopy and metrology. This article reviews some of the most
important protocols for universal quantum logic with trapped neutrals, as well as
the history and state-of-the-art of experimental work to implement these in the
laboratory. Some general observations are made concerning the different strat-
egies for qubit encoding, transport and interaction, including trade-offs between
decoherence rates and the likelihood of two-qubit gate errors. These trade-offs
must be addressed through further reﬁnements of logic protocols and trapping
technologies before one can undertake the design of a general-purpose neutral-
atom quantum processor.
KEY WORDS: Quantum information processing; neutrals atoms; controlled col-
lisions; optical lattice.
PACS: 03.67.Lx; 32.80.Pj; 34.50.-s.
An important lesson from 20th-century information science is that “infor-
mation is physical”. One cannot understand the power of algorithms,
communication protocols or other information processing tasks separately
from the physical description of the devices that perform them. In particu-
lar, quantum systems allow the implementation of new types of logic that
cannot be efﬁciently simulated on classical systems governed by laws based
Optical Sciences Center, University of Arizona, Tucson, AZ 85721, USA; E-mail:
Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM
To whom correspondence should be addressed.
1570-0755/04/1000-0091/0 © 2004 Springer Science+Business Media, Inc.