85 research outputs found
Strong violations of Bell-type inequalities for Werner-like states
We investigate the violation of Bell-type inequalities for two-qubit
Werner-like states parametrized by the positive parameter 0<p<1. We use an
unbalanced homodyne detection scheme to obtain the quantum mechanical
probabilities. A violation of the Bell-Wigner and Janssens inequalities is
obtained for a large range of the parameter p. The range given by these
inequalities is greater than the one given by the Clauser-Horne inequality. The
range in which a violation is attained actually coincides with the range where
the Werner-like states are known to be nonseparabel, i.e., for p>1/3. However,
the improvement over the Clauser-Horne inequality is achieved at the price of
restricting the class of possible local hidden variable theories.Comment: Revised manuscript, accepted for publication in PR
Enhancing image contrast using coherent states and photon number resolving detectors
We experimentally map the transverse profile of diffraction-limited beams
using photon-number-resolving detectors. We observe strong compression of
diffracted beam profiles for high detected photon number. This effect leads to
higher contrast than a conventional irradiance profile between two Airy
disk-beams separated by the Rayleigh criterion.Comment: 7 pages, 3 figures, accepted for publication in Optics Expres
Generation of Entangled N-Photon States in a Two-Mode Jaynes-Cummings Model
We describe a mathematical solution for the generation of entangled N-photon
states in two field modes. A simple and compact solution is presented for a
two-mode Jaynes-Cummings model by combining the two field modes in a way that
only one of the two resulting quasi-modes enters in the interaction term. The
formalism developed is then applied to calculate various generation
probabilities analytically. We show that entanglement, starting from an initial
field and an atom in one defined state may be obtained in a single step. We
also show that entanglement may be built up in the case of an empty cavity and
excited atoms whose final states are detected, as well as in the case when the
final states of the initially excited atoms are not detected.Comment: v2: 5 pages, RevTeX4, minor text changes + 1 figure added, revised
version to be published in PRA, May 200
Entangled Fock states for Robust Quantum Optical Metrology, Imaging, and Sensing
We propose a class of path-entangled photon Fock states for robust quantum
optical metrology, imaging, and sensing in the presence of loss. We model
propagation loss with beam-splitters and derive a reduced density matrix
formalism from which we examine how photon loss affects coherence. It is shown
that particular entangled number states, which contain a special superposition
of photons in both arms of a Mach-Zehnder interferometer, are resilient to
environmental decoherence. We demonstrate an order of magnitude greater
visibility with loss, than possible with N00N states. We also show that the
effectiveness of a detection scheme is related to super-resolution visibility.Comment: 4 pages, 5 figures, extended introduction and minor revision
Qualitative aspects of entanglement in the Jaynes-Cummings model with an external quantum field
We present a mathematical procedure which leads us to obtain analytical
solutions for the atomic inversion and Wigner function in the framework of the
Jaynes-Cummings model with an external quantum field, for any kinds of cavity
and driving fields. Such solutions are expressed in the integral form, with
their integrands having a commom term that describes the product of the
Glauber-Sudarshan quasiprobability distribution functions for each field, and a
kernel responsible for the entanglement. Considering two specific initial
states of the tripartite system, the formalism is then applied to calculate the
atomic inversion and Wigner function where, in particular, we show how the
detuning and amplitude of the driving field modify the entanglement. In
addition, we also obtain the correctComment: 15 pages and 21 figure
PanMeMic Manifesto: Making meaning in the Covid-19 pandemic and the future of social interaction
Qubit portrait of the photon-number tomogram and separability of two-mode light states
In view of the photon-number tomograms of two-mode light states, using the
qubit-portrait method for studying the probability distributions with infinite
outputs, the separability and entanglement detection of the states are studied.
Examples of entangled Gaussian state and Schr\"{o}dinger cat state are
discussed.Comment: 20 pages, 6 figures, TeX file, to appear in Journal of Russian Laser
Researc
Effect of Adjunctive Systemic Azithromycin With Periodontal Surgery in the Treatment of Chronic Periodontitis in Smokers: A Pilot Study
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141533/1/jper1887.pd
Rapid Sampling of Molecules via Skin for Diagnostic and Forensic Applications
Skin provides an excellent portal for diagnostic monitoring of a variety of entities; however, there is a dearth of reliable methods for patient-friendly sampling of skin constituents. This study describes the use of low-frequency ultrasound as a one-step methodology for rapid sampling of molecules from the skin.
Sampling was performed using a brief exposure of 20 kHz ultrasound to skin in the presence of a sampling fluid. In vitro sampling from porcine skin was performed to assess the effectiveness of the method and its ability to sample drugs and endogenous epidermal biomolecules from the skin. Dermal presence of an antifungal drug—fluconazole and an abused substance, cocaine—was assessed in rats.
Ultrasonic sampling captured the native profile of various naturally occurring moisturizing factors in skin. A high sampling efficiency (79 ± 13%) of topically delivered drug was achieved. Ultrasound consistently sampled greater amounts of drug from the skin compared to tape stripping. Ultrasonic sampling also detected sustained presence of cocaine in rat skin for up to 7 days as compared to its rapid disappearance from the urine.
Ultrasonic sampling provides significant advantages including enhanced sampling from deeper layers of skin and high temporal sampling sensitivity
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