NASA Scientific and Technical Aerospace Reports

induced transparency (EIT) in GaAs quantum wells. Cavity QED studies are based on the development of a composite
nanocrystal-microsphere system, in which CdSe/ZnS core/shell nanocrystals couple to whispering gallery modes (WGMs) in
a fused silica microsphere. The composite microcavity system can feature a Q-factor as high as 108 and a nanocrystal
decoherence rate as small as 3 microneV (0.75 GHz), indicating that the composite system can in principle reach the strong
coupling regime of cavity QED. EIT studies have exploited the use of Coulomb interactions between excitons to induce and
manipulate exciton spin coherence and biexciton coherence. These studies have led to the first experimental demonstration of
EIT in inter-band optical transitions in semiconductors in A-type, cascaded, and V-type three-level systems.
DTIC
Q Factors; Quantum Wells; Semiconductors (Materials); Switching
20040073738 Northwestern Univ., Evanston, IL
MURI Fellow on Quantum Information Technology: Entanglement, Teleportation, and Quantum Memory
Kumar, Prem; Sharping, Jay E.; Jan. 31, 2004; 5 pp.; In English
Contract(s)/Grant(s): DAAD19-00-1-0469
Report No.(s): AD-A422655; ARO-41618.7-PH-MUR; No Copyright; Avail: CASI; A01, Hardcopy
This grant supported a MURI Fellow to work on topics in the area of Quantum Information Technology. Specifically, Jay
E. Sharping worked on the following research tasks: i) Generation of polarization-entangled photon-pair pulses near 1.5
micron wavelength by use of the Kerr nonlinearity of standard dispersion-shifted optical fiber and ii) applying the same
techniques to obtain polarization- entangled photon-pair pulses near the 0.8 micron wavelength by use of novel
micro-structured optical fibers (also called holey fibers). In both cases, nondegenerate four-wave mixing was used to
simultaneously generate signal/idler photon pairs. Thorough studies of the classical nonlinear optical processes were
performed and several useful applications such as parametric amplification, parametric oscillation, and all- optical switching
were demonstrated. Direct detection and photon counting techniques were used to experimentally verify quantum-correlated
signal/idler pair production. Photon counting tools for detection at wavelengths of 1.5 micron were built and characterized.
Time and polarization multiplexed four-wave mixing processes were then used to generate polarization-entangled photon
pairs, and the quality of the entanglement was evaluated through quantum interference and Bell-inequality-violation
measurements.
DTIC
Quantum Optics
20040073740 Air Force Research Lab., Edwards AFB, CA
A Novel Wave Front Method Used for Tracking Terrestrial Concentrator Focal Spot Location
Beasley, Joseph N.; Mar. 26, 2004; 13 pp.; In English
Contract(s)/Grant(s): Proj-1011
Report No.(s): AD-A422658; No Copyright; Avail: CASI; A03, Hardcopy
This paper presents a new sensing method for tracking terrestrial concentrator focal spot location. The new method
utilizes the shape and mirror-like surfaces of the absorber as a wave front sensor. The paper begins with a discussion of wave
front sensing and how it can be used in optical systems to measure phase differences in light waves across an aperture. The
wave front sensing method is then modified from an aperture or lens system into a mirror system. After the method wa-s
developed for mirrors, it was developed into a method of detecting focal spot location errors.
DTIC
Concentrators; Position (Location); Wave Fronts
20040073809 Stanford Univ., Stanford, CA
Research Studies on Electromagnetically Induced Transparency
Harris, Stephen E.; Apr. 2004; 11 pp.; In English
Contract(s)/Grant(s): DAAD19-01-1-0028
Report No.(s): AD-A422836; ARO-41376.15-PH; No Copyright; Avail: CASI; A03, Hardcopy
The final report describes progress in the use of electromagnetically induced transparency for the realization of new types
of nonlinear interactions and processes. We have worked in two areas: (1) The generation of femtosecond pulses by phased
and anti-phased molecular states and the use of this radiation for new types of physical processes, and (2) The demonstration
of elementary nonlinear optical processes at low- light-levels. Highlights of the work on this program include the suggestion
and first demonstration of the use of an EIT- like Raman process to produce a spectrum with a width over 50, 000 cm-1 of
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