### QUANTUM TECHNOLOGIES

**A Proposed Continuation of an FY97 One-Year LDRD/CD Thrust**

**[D. J. Vieira]{.underline}, W. P. Ambrose, E. P. Chamberlin, S. Crane,
R. Guckert, R. K. Sander, X. Zhao**

**Chemical Science and Technology Division**

**[R. J. Hughes]{.underline}, D. Bowman, S. Brice, W. Buttler, A.
Goldschmidt, M. S. Gulley, A. Hime, M. H. Holzscheiter, N. Kurnit, P.
Kwiat, S. Lamoreaux, V. D. Sandberg, M. M. Schauer, D. Tupa**

**Physics Division**

**Other Participants:**

**J. M. Ettinger (NIS-9), B. L. Fearey (NIS-7), D.F.V. James (T-4), P.
W. Milonni (T-4), M. Neergaard (NIS-9)**

\*\*\*\*\*\*\*

**Core Competencies: Nuclear Science, Plasmas, and Beams**

**Theory, Modeling, and High Performance Computing**

**Program Offices: STB/ER**

**NIS/IT & NIS/RD**

**DoD**

**Funding Request: \$ 1M/year for 4 years**

## Summary

Recent developments in quantum optics and the laser cooling / trapping
of atoms and ions have made a variety of innovative scientific and
technological uses of quantum systems experimentally accessible. Last
year the "Trapping and Laser Manipulation of Trapped Species" proposal
from CST Division and the "Quantum Information Science" proposal out of
P Division were merged and given exploratory, one-year funding under the
name "Quantum Technologies" to develop these experimental techniques.
Five examples which show the power of quantum technologies are in
progress:

-   Laser manipulation of the quantum states of trapped calcium ions
    provides an environment for investigating quantum computation. The
    massive computational parallelism afforded by the superposition
    principle provides quantum computation with the potential to render
    "public key" encryption systems insecure;

-   In the emerging technology of quantum cryptography the
    indivisibility of quanta allows secret communications to be
    established through single-photon transmissions even in the presence
    of hostile monitoring;

-   Interaction-free measurements allow an object to be detected quantum
    mechanically without scattering or absorption of radiation;

-   Magneto-optical trapping of Rb and Cs atoms opens up new
    experimental tests of electroweak interactions and applications to
    the ultra-sensitive detection of NBC proliferates;

-   Atomic fountain / atom interferometry offers a new method of
    detecting hidden underground structures.

Over the last year these projects have grown into an effective
multi-divisional collaboration and we have made good progress that has
opened up a variety of forefront basic science research possibilities as
well as practical applications that are important to the Laboratory. We
propose to continue these efforts to dramatically increase the
Laboratory's capabilities in these areas with a set of highly
synergistic basic science, information assurance, nonproliferation and
national security projects involving multi-quantal systems as outlined
below.

In the area of great science we propose to investigate: (1) the
foundations of quantum mechanics for multi-quantal systems in previously
inaccessible domains (i.e. in Hilbert spaces of greater than 4
dimensions); (2) parity violation or parity and time reversal violation
in a set of high-precision electroweak interaction measurements; and (3)
the properties of coherent cold atoms using the latest in Bose-Einstein
condensate / atom laser technology. Applications of quantum technologies
include: (1) assessing the cryptanalytic potential and limitations of
quantum computation, and its impact on information assurance; (2)
constructing prototype quantum cryptography systems; (3) determining the
capabilities of interaction-free techniques for detecting "stealthy"
objects; (4) developing ultra-sensitive trapped-atom techniques for
detecting NBC proliferates; and (5) an atom interferometer for
gravity-gradiometric detection of underground structures.

These projects are truly state-of-the-art: they "push the envelope" in
basic and applied research. As such, this proposal represents one of the
most exciting science and technology opportunities for Los Alamos.
Furthermore, the Laboratory is exceptionally well-placed to become the
leader in this emerging field of quantum technology given our unique
combination of world-class expertise and proven record of
accomplishments.

This proposal is well aligned with the STB/ER, NIS, and DoD program
office missions, and the core competencies of Nuclear Science, Plasmas
and Beams; and Theory, Modeling, and High Performance Computing. This
work draws on a diverse array of Laboratory strengths in: atomic and
nuclear science, quantum optics, laser technology, separations
chemistry, and security applications; and it involves a close
collaboration between CST- and P-Division personnel and university
collaborators. We believe that it is important to undertake this quantum
technology research program because it will position the Laboratory to
effectively address vitally important national security issues as we
enter the 21st century, while stretching our scientific capabilities in
a direction that will enhance our status as a world-class scientific
organization.

**[Introduction: Importance of Quantum Technology to the
Laboratory]{.underline}**

In the past few years there have been advances in the experimental study
of the foundations of quantum mechanics, photonics, and atomic science
that make it possible: to produce non-classical two-photon states; to
laser cool atoms and ions to their quantum mechanical (motional) ground
states; and to optically manipulate these quantum states. These
revolutionary methods have opened up a wide-variety of novel concepts in
previously inaccessible physical domains to experimental investigation.
During the last year our collaboration has jointly developed
experimental techniques whose common goal is to exploit these
multi-quantal capabilities. (At the purely technical level, other common
themes of these activities are: traps, narrow linewidth diode laser
technology, and frequency up- and down-conversion.) These breakthrough
technologies open up a wide range of research that is important to the
Laboratory in three main areas: basic science; quantum computation and
information assurance; and nonproliferation and international security.

There are several reasons why this thrust is important to the
Laboratory. The research program proposed below builds on our existing
multi-divisional expertise in: atomic and nuclear science, quantum
optics, laser technology, separation chemistry, and security
applications. It is well aligned with the STB/ER, NIS, and DoD program
office missions, and the core competencies of Nuclear Science, Plasmas,
and Beams, and Theory, Modeling, and High Performance Computing.
Furthermore, the proposed work is great, innovative science with
real-world applications that expand our capabilities and strengthen our
science and technology base. We anticipate many publishable results with
a major impact in the international scientific community. Moreover, the
proposed research offers to produce new technologies for: information
security in optical networks and satellite communications; information
warfare (code breaking) and information assurance (security of US
cryptosystems); advanced computation; new techniques for detection of
stealthy objects; ultra-sensitive detection capabilities for nuclear
proliferates; and a new method of detecting hidden underground
structures. These technologies are of great interest to and address
urgent needs in the intelligence and defense communities. The prospects
for this research to produce new funding and follow-on projects appear
to be very good. (Of particular interest to potential sponsors, and in
contrast to our competitors, we have the ability to perform components
of this work at a classified level if necessary.) The advancement of
this key technology is simply something that the Laboratory needs. It
has broad applicability and at this time it is one of the hottest
scientific opportunities around.

The Laboratory is extraordinarily well-placed to become an international
leader in this important field, if we act now. We already have a solid
foundation of on-going projects on which to build a program to study the
wealth of quantum technology applications. Moreover, we are established,
internationally recognized researchers in this new field, with a
demonstrated record of pioneering achievements, and we have the diverse
ex­pertise in, and synergy between all the relevant aspects of
experimental science and security applications that are required for
success in this endeavor. It is strong evidence for the importance of
quantum technology research and the strength of our capabilities that we
have received significant funding from within the intelligence and
nonproliferation communities for specific (narrowly focused) tasks.
However, this funding is programmatically directed toward (and adequate
for) the very specific project deliverables, and so does not provide the
resources to fully realize the potential of quantum technologies at the
Laboratory. Therefore, we request LDRD thrust funding of \$1M/year for
four years to establish a coherent, broad-based, multi-disciplinary
program which will have as its goal the development of quantum
technology tools and the exploration of their potential applications.
Below we outline a well-balanced mix of basic and applied science
opportunities worthy of continued LDRD CD thrust investment by the
Laboratory.

**[Science and Technology Objectives]{.underline}**

**A. Great Science**

**1. Fundamental Quantum Mechanics**

In the early 1980s Feynman and others developed a new perspective on
quantum mechanics involving information science concepts. He considered
the representation of binary numbers by orthogonal quantum states (\|0\>
or \|1\>) of a two-level quantum system. (A single bit of information in
this form is known as a "qubit.") This new paradigm opens up novel
possibilities. A qubit can be prepared in a coherent superposition of
both values at once: \|ψ\> = cos θ\|0\> + sin θ\|1\>, but even more
unusual quantum states can be produced with two qubits. In so-called
"entangled" states such as \|ψ\> = 2-1/2(\|0\>\|0\> + \|1\>\|1\>)
neither qubit has a definite value, but nevertheless both qubits have
the same value. Such non-classical states of two or more qubits could be
created with quantum logical "gate" operations, which are also the
building blocks of a quantum computer.

The concept of computing with quantum-mechanical superpositions of
numbers, known as quantum parallelism, makes quantum computation in
principle very much more powerful than classical computation because it
allows an extraordinarily large number of computations to be performed
simultaneously. We have recently succeeded in trapping calcium ions in a
quantum computational device. The qubits will be the ground state and a
metastable (long-lived) excited state of these calcium ions, isolated
from the environment and localized in an ion trap. Bit-wise quantum
logical operations will be effected with a laser beam, resonant with the
qubit transition frequency, directed at each ion. Our near-term goals
are to: (1) demonstrate the sideband cooling of a string of Ca ions to
the quantum ground state of their center of mass motion; (2) create
quantum states of the ions' motion and perform quantum logical
operations (gates); and (3) demonstrate simple quantum computations.

We have received significant external funding for the development of
this ion trap system. This funding is adequate for the narrowly focused
programmatic deliverables, but we also foresee a much broader use of
this quantum computing device. Because a quantum computer provides an
operational method of producing arbi­trary quantum states from simple
gate operations it offers the prospect of novel experiments in the
foundations of quantum mechanics. We propose to gener­ate entangled
states of several qubits, and to investigate experimentally for the
first time nonclassical quantum behavior with more than two particles.
The gate operations will also allow us to implement ex­perimental quantum
error correction and thus to demonstrate that quantum information can be
preserved in spite of decoherence. The creation of quantum states of
motion of several ions will also be possible, including "Schroedinger
cat states" in which the ions' motion will be in a macro­scopic
superposition. By using such states we will investigate the relationship
between the quantum and classical worlds as never before possible.

Entangled states of two photons can be directly produced when a laser
beam impinges on a suitable non-linear crystal via the phenomenon known
as parametric down-conversion. We have extensive expertise in this area.
Experiments to date have focused on particles entangled in a *single*
degree of freedom, e.g., polarization, energy, or momentum direction.
Using a modification of previous arrangements, we propose to prepare
"hyper-entangled" photon pairs that are simultaneously entangled in
polarization, momentum-direction, and energy; and an even more general
class of states, so-called "nonmaximally entangled" states, in which the
amplitudes of the contributing terms have different magnitudes. Owing to
the larger associated Hilbert space, these more general states allow
certain quantum-mechanical operations to be performed that are otherwise
virtually impossible.

A particularly useful tool in these investigations will be very high
efficiency single-photon detectors. We propose to continue an existing
study and development of detectors produced by Rockwell with a
single-photon detection efficiency at the relevant wavelengths in excess
of 90% and a unique capability of distinguishing the actual number of
photons simultaneously incident. These detectors will be used for
quantum information experiments, including a defini­tive test of quantum
nonlocality (Bell's inequalities). Because down-conversion photons are
useful for many practical applications, ranging from quantum
cryptography to absolute radiometric measurements, a convenient source
of them is desirable. Using existing technologies, we propose to produce
an all-solid-state down-conversion source that is much smaller,
convenient and cheaper than existing sources.

Another area of great interest is that of "interaction free
measurement," in which the existence of absorbing objects can be
ascertained with arbitrarily small absorption tak­ing place. We have
already demonstrated an 85% interaction-free scheme, relying on the
inhibition of interfer­ence. Paradoxically, it is the very *presence* of
the absorbing object which alters the quantum state of the interrogating
particle to ensure that it is only rarely absorbed. We now propose to
extend the method to permit interaction-free *imaging* of objects. In
particular, we believe that this could be very useful for studying
fragile objects or even quantum objects such as Bose-Einstein
condensates.

**2. Electroweak Interactions**

We will apply optical and magnetic trapping technology to the
concentration, confinement, and polarization of selected atoms for
high-precision, electroweak interaction measurements. In the charged
current sector, we are working on a beta-spin correlation measurement of
82Rb to examine parity violation more carefully and to search for new
physics, such as the existence of right-handed currents, and to
characterize recoil order effects (e.g. weak magnetism). High-precision
measurements in the 10^-3^ range will be made possible using the
combination of mass separator, optical trap, magnetic trap, beta and
recoil ion detectors. During the past year we have been successful in
coupling an optical trap to a mass separator, obtaining a 20% trapping
efficiency, and designing and modeling the magnetic trap and detection
system. We are looking forward to undertaking our first beta-asymmetry
measurement in the coming year.

In the neutral current sector, we will use an optical trap to undertake
atomic parity nonconservation (PNC) measurements in a series of Cs and
Fr radioisotopes. PNC measurements at the level of 2 x 10^-3^, our
intended goal, will constrain the Standard Model at the same level as
current Z^0^ results do today, but in a much different energy regime
(eVs instead of GeVs) where uncertainties associated with the isospin
non-conserving radiative corrections and the mass of the top quark are
greatly diminished. Moreover, these PNC measurements will enable the
nuclear anapole moment, the leading parity violating moment of the
nucleus, for a series of isotopes to be systematically characterized for
the first time. Both the PNC and the beta-asymmetry experiments are of
world-class caliber.

Finally, the development of these trapping technologies will enable a
new search for the permanent electric dipole moment (EDM) of an atom -
an effect that violates time reversal symmetry. At present, the only
known example of time reversal asymmetry is in the decay of the K0
meson. This is not understood and theories put forward to explain this
process have been rigorously tested, and most eliminated, over the last
30 years, principally by EDM limits for the neutron and for the 199Hg
atom. Recent theoretical analysis of octapole deformed nuclei, such
225Ra, indicates that T-violating nucleon-nucleon interactions can lead
to a greatly enhanced EDM for such atoms which are roughly 100 times
larger than for the bare neutron or 10,000 larger than for the 199Hg
atom. Given the quantum technology developments mentioned herein and the
Laboratory's ability to separate and handle highly radioactive samples,
such as 229Th which feeds 225Ra through alpha decay, we are uniquely
situated to undertake an atomic fountain EDM experiment for 225Ra which
is expected to yield a 2-3 orders of magnitude increase in sensitivity
over present limits. The sensitivity to the T-violating part of the
nucleon-nucleon interaction for the 225Ra EDM experiment is expected to
be comparable to that of a new neutron EDM experiment being planned for
the Long Pulse Spallation Source.

**3. Bose-Einstein Condensates and the Atom Laser**

By combining laser cooling and trapping technologies with evaporative
cooling, the first observation of Bose-Einstein condensates (BEC) in a
dilute atomic vapor was demonstrated by Carl Wieman (one of our
collaborators), Eric Cornell et al. from the University of Colorado /
JILA in 1995. Predicted by Einstein over 70 years ago, BEC occur when a
collection of atoms with integral total spin ("bosons") are cooled (well
below 170 nK in the above case) to their lowest energy quantum state
thus losing their individual identities and condensing into a coherent
set of atoms all with a common wavefunction. Although other
"macroscopic" systems exhibiting quantum degeneracy (in particular,
superfuild helium and superconductivity in metals) have been studied,
the production of BEC in weakly interacting atomic vapor system opens up
an entire new field of investigation - that of the quantum mechanical
and quantum statistical nature of macroscopically coherent systems. Very
recently an MIT group has expelled a BEC out of their magnetic trap to
produce a coherent atom source called the atom laser. It is anticipated
that this cold and very bright source of coherent atoms will have many
scientific and technological applications and Los Alamos would be wise
to position itself to take advantage of this emerging technology.
Because an alkali vapor BEC / atom laser system is built upon the same
technology that we are developing for the electroweak interaction
measurements, we will have the capability of developing our own BEC /
atom laser system. Initial measurements that interest us are an
interference experiment to prove BEC ensemble phase coherence and the
sympathetic cooling of Fermionic sister systems, such as 82Rb, by BEC.
An exciting application worthy of exploration is the development of
atom-laser nanolithography to further miniaturize semiconductor chips.
Dramatic gains in resolution (\~100 times improvement) are, in
principle, possible due to the much shorter de Broglie wavelength of
cold, coherent atoms as compared to that of UV light

**B. Quantum Computation and Information Assurance**

Algorithmically hard problems such as the factorization of integers into
their prime factors, which is the basis for the security of modern
public key cryptosystems, could be solved efficiently on a quantum
computer. A quantum computer running at desktop PC speeds could break
the keys of these cryptosystems in only seconds as opposed to the months
or years required with conventional computers. It is therefore very
important for both the assurance of continued information security and
the possible development of new cryptanalytical technology to determine
if quantum computation is feasible and if so, to fully understand its
capabilities and limitations. We propose to assess the potential and
limitations of quantum computation by investigating the relevant
coherence times and the precision of quantum logic operations in our ion
trap system.

The potential development of quantum computers necessitates the
corresponding development of efficient quantum algorithms. To date, only
a few quantum algorithms which efficiently solve classically intractable
problems are known. Remarkably, all use the Quantum Fourier Transform
(QFT) as a basis for the algorithm. With these facts in mind, we propose
to concentrate our algorithmic efforts in the following three
directions: 1) increase the efficiency of known quantum algorithms by,
for example, implementing fast multiplication methods in the quantum
factoring algorithm; 2) develop further applications of the QFT to such
problems as network optimization; 3) research extensions of the QFT to
non-abelian groups, which could allow efficient solution of "graph
isomorphism" and other problems.

If quantum computation may render existing cryptographic methods
insecure, quantum cryptography offers a new level of unrivaled
information security. The encryption of messages to render them
unintelligible to third parties can be accom­plished if the sender and
recipient use a secret random bit sequence, known as "key" material, to
encrypt and decrypt their communications. However, the initial step of
key distribution, in which the two parties acquire the key material,
must be accomplished securely. Quantum cryptography is a method for key
distribution with single-photon transmissions whose se­curity is based on
the inviolability of the laws of quantum mechanics. For example, an
adversary cannot "tap" the key transmissions owing to the indivisibility
of quanta. We have recently demonstrated experimentally that quantum
cryptography is feasible using single-photon inter­ference states over 48
km of optical fiber between two LANL Technical areas. (This experiment
indicates that propagation dis­tances of up to 100 km should be
possible.) In a separate project we are studying whether quantum
cryptography will be feasible for surface-to-satellite and
surface-to-aircraft communications using single-photon polarization
states. We have already achieved a propagation distance of 205 m. These
experiments are sufficiently encouraging that we now propose to take
quantum cryptography from the experimen­tal to the prototype stage.
Specifically, we propose to develop the hardware and software necessary
for quantum cryptography systems to continuously generate cryptographic
key material in unattended mode. The reliability and secrecy of the key
material obtained by quantum cryptography depends on subsequent "data
reconciliation" and "privacy amplifi­cation" protocols over a public
channel. We propose to study how to maximize the secrecy capacity by
adopting an integrated quantum/public channel analysis of the privacy
amplification, reconciliation, and de­tector efficiency issues.
Furthermore, we propose to study the use of adaptive optics for
enhancing the data rate in free-space.

Our recent successful demonstration of 85% interaction-free measurements
raises the possibility that this quantum physical phenomenon could be
adapted to detect "stealthy" objects that are not readily detectable by
scattering or absorption of radiation. We propose to study this
possibility by first investigating an interaction-free "magic eye"
system for intrusion detection.

**C. Nonproliferation and National Security**

**1. Ultra-Sensitive Detection of Selected NBC Proliferates**

Because the process of optical trapping involves the repeated near
resonant absorption and fluorescence of millions of photons per second,
the inherent isotopic and elemental selectivity and detection
sensitivity of an optical trap is inherently high. A near term goal is
to pioneer is the quantitative detection of selected, long-lived
radioactive species, such as 135Cs, 137Cs, and 90Sr, which are of
interest to nuclear nonproliferation and treaty verification concerns.
Several orders of magnitude gain in threshold sensitivity compared to
conventional methods appear possible. Beyond our basic approach
involving the ion implantation and heated release of atoms from a thin
foil, we will also explore the possibility of using laser ablation to
inject a broader range of atomic species into the trap. Potential
advantages of this process include the controllable injection of atoms
into a small (\~1 cm^3^) volume so that high efficiencies with small
samples can be obtained and the possible direct production of metastable
species with optical transitions amenable to trapping (e.g. noble
gases). This method may also make possible the photochemical generation
of trapable atoms from molecular precursor and facilitate the trapping
of refractory element species. These developments would have important
applications in the nuclear, biological, and chemical (NBC) detection
arena.

**2. Atom Interference Gravity Gradient Detection of Underground
Structures**

Impressive strides in measuring the acceleration due to gravity, g, have
recently been made through the use of laser-cooled atom traps and atomic
fountain atom interferometry. In this free-fall type experiment, the
Ramsey interference method is used to accurately measure the Doppler
velocity change of cold, low-velocity atoms as they travel up and down
in an atomic fountain. Although absolute g determinations at the
demonstrated accuracies of 10^-8^ (future improvements could obtain
10^-10^) are sufficient (given adequate height, topographic and local
mass distribution information) to detect underground structures, a more
practical approach is through the measurements of gravity gradients. The
spatial variations of these gradients in the vicinity of hidden
underground structures could be measured using cold atoms from two
spatially separated optical traps with a common laser system. Placed on
a moving platform, such a system would offer a combination of rapid
measurement rates and high detection sensitivities that are not
currently possible with conventional, bulk-matter gravity gradient
measurement methods. During the past year a study group composed of
scientists from CST, P, EES, and NIS Divisions have carefully
scrutinized and suggested refinements to the atom interferometry method
and we have formed a collaboration with Mark Kasevich from Stanford
University with the goal of making a fieldable prototype. The
advancement of quantum technologies at the Laboratory will greatly
facility the development of such a gravity gradiometer which is of high
interest to the intelligence community.

**[Milestones & Schedule]{.underline}**

FY98: Quantum states of motion of trapped ions; generation of novel
"hyper- entangled" two-photon states; interaction-free imaging; first
beta-asymmetry measurement on trapped 82Rb; quantitative detection of
radioactive 135Cs and 137Cs atoms.

FY99: Quantum state engineering with trapped ions; loophole-free test of
quantum non-locality; demonstrate trapping of 221Fr/225Ra for PNC/EDM
experiments; construct lab-based atom interferometer; improve
ultra-sensitive detection capabilities & extend to other species.

FY00: Production of all-solid-state down-conversion source; quantum
mechanics experiments with multi-quantal ion states; begin PNC or EDM
measurement; field test ultra-sensitive detection system.

FY01: Quantum state amplification via interaction-free measurements;
refine PNC or EDM experiment; undertake coherent atom or sympathetic
cooling experiment; field test atom interference gravity gradiometer.

+-------------------+-----------+-----------+-----------+------------+
| **Project**       | **FY98**  | **FY99**  | **FY00**  | **FY01**   |
+-------------------+-----------+-----------+-----------+------------+
| Fund. Quantum     | **XXXX**  | **XXX**   | **XXX**   | **XX**     |
| Mechanics         |           |           |           |            |
+-------------------+-----------+-----------+-----------+------------+
| Electroweak       | **XXX**   | **XXX**   | **XXX**   | **XXX**    |
| Interactions      |           |           |           |            |
+-------------------+-----------+-----------+-----------+------------+
| BEC / Atom Laser  |           | **XX**    | **XX**    | **XXX**    |
+-------------------+-----------+-----------+-----------+------------+
| Quantum Computer  | **XX**    | **XX**    | **XXX**   | **XXX**    |
| & Information     |           |           |           |            |
| Assurance         |           |           |           |            |
+-------------------+-----------+-----------+-----------+------------+
| Ultra-Sensitive   | **XX**    | **XX**    | **XX**    |            |
| Detection         |           |           |           |            |
+-------------------+-----------+-----------+-----------+------------+
| Atom Interference | **X**     | **XX**    | **XX**    | **XXX**    |
|                   |           |           |           |            |
| Gravity           |           |           |           |            |
| Gradiometer       |           |           |           |            |
+-------------------+-----------+-----------+-----------+------------+

X's indicate degree of effort (XXXX = activity in all four quarters of
the year).

**[Appendix: Brief Background Information]{.underline}**

**David Vieira** is the project leader and principal investigator for
the atom trapping effort at Los Alamos. He received his B.S. degree in
chemistry in 1972 and went on to obtain his Ph.D. in nuclear chemistry
from the University of California, Berkeley in 1978. After a
post-doctorate appointment in the nuclear chemistry group at Los Alamos,
he was hired as a staff member into the same group in 1979. Since then
he has served as section leader ('85-'91), team leader ('91-95), and
project leader ('95-). Concurrently, Dr. Vieira has served as an Adjunct
Professor of Physics at the Utah State University since 1984. In 1990-91
he took professional research and teaching leave from the Laboratory and
pursued radioactive beam / exotic nuclei research in Darmstadt, Germany
as an Alexander von Humboldt Fellow. In 1993 Dr. Vieira received a LANL
distinguished performance award. His current research interests include
high-precision measurements of electroweak interactions in nuclei,
optical trapping, atomic and laser science, radioactive beams/exotic
nuclei, and the application of nuclear and laser techniques to
nonproliferation and national security issues. He is the author of over
70 scientific papers.

**Richard Hughes** is Quantum Information Science team leader and
principal investigator of experimental and mathematical quantum
computation projects as well as projects in quantum cryptography over
optical fibers and for satellite communications. He obtained his Ph.D.
in Theoretical Elementary Particle Physics from the University of
Liverpool, England in 1978 and has held research positions at: Oxford
University and The Queen's College, Oxford; the California Institute of
Technology; and CERN, Geneva, Switzerland. He has published over 80
scientific papers, concerning the foundations of quantum mechanics,
precision tests of fundamental symmetries, and gravitation. He has held
distinguished visiting scientist positions at Oxford University (Dr. Lee
Fellow, Christ Church, 1994) and at the University of Oslo, Norway
(1993).

**Paul Kwiat** has been a J. R. Oppenheimer Fellow at LANL since August
1995. He obtained his Ph.D (specializing in Quan­tum Optics) from the
University of California, Berkeley in 1993 and spent the interim as a
Lise-Meitner Fellow at the University of Innsbruck. His work has been
featured in numerous popular articles, and he has published nearly 40
scien­tific papers on topics including tests of quantum nonlocality,
demonstrations of novel two-photon interference effects,
photon-tunneling time measurements, and the development of
"interaction-free measurement" techniques. He has pio­neered novel
techniques for correlated-photon generation, manipulation and analysis.

**Steve Lamoreaux** has been a staff member at LANL since December 1996.
He received his B.S. in Physics in 1981 from the University of
Washington in Seattle, M.S. in Physics from the University of Oregon in
1982, and Ph.D. from the University of Washington in 1986 (awarded the
Henderson Prize for an outstanding dissertation). Upon completion of the
Ph.D., he took a postdoctoral position at the Univ. of Washington and
eventually attained the academic rank of Research Associate Professor,
and was named a Fellow of the American Physical Society in 1996. He has
been a long-term visiting scientist at the Institut Laue-Langevin in
Grenoble, France, and at the Hahn-Meitner Institut in Berlin, Germany.
His primary work has been in experimental radiofrequency and laser
atomic spectroscopy, semiconductor diode laser development, liquid state
studies using laser light scattering, precision tests of fundamental
physical interactions and quantum mechanics using neutrons and atomic
systems, general atomic theory, theoretical and experimental study of
noise, and neutron-matter interaction theory and experiment,
particularly for the case of ultracold neutrons. He has published about
40 papers, co-authored two books, and has written several review
articles.