6,942 research outputs found
Leveraging Employer Practices in Global Regulatory Frameworks to Improve Employment Outcomes for People with Disabilities
Work is an important part of life, providing both economic security and a forum to contribute one’s talents and skills to society, thereby anchoring the individual in a social role. However, access to work is not equally available to people with disabilities globally. Regulatory environments that prohibit discrimination and support vocational training and educational opportunities constitute a critical first step toward economic independence. However, they have not proven sufficient in themselves. In this article, we aim to infuse deeper consideration of employer practice and demand-side policy reforms into global policy discussions of the right to work for people with disabilities. We begin by documenting the employment and economic disparities existing for people with disabilities globally, followed by a description of the international, regional, and local regulatory contexts aiming to improve labor market outcomes for people with disabilities. Next, we examine how policies can leverage employer interests to further address inequalities. We discuss employer policies and practices demonstrated in the research to facilitate recruitment, hiring, career development, retention, and meaningful workplace inclusion. The goal of the article is to synthesize existing international literature on employment rights for people with disabilities with the employer perspective
Operational Discord Measure for Gaussian States with Gaussian Measurements
We introduce an operational discord-type measure for quantifying nonclassical
correlations in bipartite Gaussian states based on using Gaussian measurements.
We refer to this measure as operational Gaussian discord (OGD). It is defined
as the difference between the entropies of two conditional probability
distributions associated to one subsystem, which are obtained by performing
optimal local and joint Gaussian measurements. We demonstrate the operational
significance of this measure in terms of a Gaussian quantum protocol for
extracting maximal information about an encoded classical signal. As examples,
we calculate OGD for several Gaussian states in the standard form.Comment: 18 pages, 3 figure
Sufficient Conditions for Efficient Classical Simulation of Quantum Optics
We provide general sufficient conditions for the efficient classical
simulation of quantum-optics experiments that involve inputting states to a
quantum process and making measurements at the output. The first condition is
based on the negativity of phase-space quasiprobability distributions (PQDs) of
the output state of the process and the output measurements; the second one is
based on the negativity of PQDs of the input states, the output measurements,
and the transition function associated with the process. We show that these
conditions provide useful practical tools for investigating the effects of
imperfections in implementations of boson sampling. In particular, we apply our
formalism to boson-sampling experiments that use single-photon or
spontaneous-parametric-down-conversion sources and on-off photodetectors.
Considering simple models for loss and noise, we show that above some threshold
for the probability of random counts in the photodetectors, these
boson-sampling experiments are classically simulatable. We identify mode
mismatching as the major source of error contributing to random counts and
suggest that this is the chief challenge for implementations of boson sampling
of interesting size.Comment: 12 pages, 1 figur
Verification of quantum discord
We introduce a measurement-based method for verifying quantum discord of any
bipartite quantum system. We show that by performing an informationally
complete POVM (IC-POVM) on one subsystem and checking the commutativity of the
conditional states of the other subsystem, quantum discord from the second
subsystem to the first can be verified. This is an improvement upon previous
methods, which enables us to efficiently apply our method to
continuous-variable systems, as IC-POVMs are readily available from homodyne or
heterodyne measurements. We show that quantum discord for Gaussian states can
be verified by checking whether the peaks of the conditional Wigner functions
corresponding to two different outcomes of heterodyne measurement coincide at
the same point in the phase space. Using this method, we also prove that the
only Gaussian states with zero discord are product states; hence, Gaussian
states with Gaussian discord have nonzero quantum discord.Comment: 5 page
Correlation of the Hippocampal theta rhythm to changes in hypothalamic temperature
Warming and cooling the preoptic anterior hypothalamic area in awake, loosely restrained rabbits was found to evoke theta rhythm. This is consistent with previous studies indicating that theta rhythm is a nonspecific response evoked by stimulation of several sensory modalities. Several studies have correlated theta rhythm with alertness. A neural pathway involving the hypothalamus, the hippocampus, the septal area, and the reticular formation is proposed. Thus, a role of this pathway may be to alert the animal to changes in its body temperature
Impact-ionization and noise characteristics of thin III-V avalanche photodiodes
It is, by now, well known that McIntyre\u27s localized carrier-multiplication theory cannot explain the suppression of excess noise factor observed in avalanche photodiodes (APDs) that make use of thin multiplication regions. We demonstrate that a carrier multiplication model that incorporates the effects of dead space, as developed earlier by Hayat et al. provides excellent agreement with the impact-ionization and noise characteristics of thin InP, In/sub 0.52/Al/sub 0.48/As, GaAs, and Al/sub 0.2/Ga/sub 0.8/As APDs, with multiplication regions of different widths. We outline a general technique that facilitates the calculation of ionization coefficients for carriers that have traveled a distance exceeding the dead space (enabled carriers), directly from experimental excess-noise-factor data. These coefficients depend on the electric field in exponential fashion and are independent of multiplication width, as expected on physical grounds. The procedure for obtaining the ionization coefficients is used in conjunction with the dead-space-multiplication theory (DSMT) to predict excess noise factor versus mean-gain curves that are in excellent accord with experimental data for thin III-V APDs, for all multiplication-region widths
Performance of Photon-Pair Quantum Key Distribution Systems
We analyze the quantitative improvement in performance provided by a novel
quantum key distribution (QKD) system that employs a correlated photon source
(CPS) and a photon-number resolving detector (PNR). Our calculations suggest
that given current technology, the CPR implementation offers an improvement of
several orders of magnitude in secure bit rate over previously described
implementations
Discriminating quantum-optical beam-splitter channels with number-diagonal signal states: Applications to quantum reading and target detection
We consider the problem of distinguishing, with minimum probability of error,
two optical beam-splitter channels with unequal complex-valued reflectivities
using general quantum probe states entangled over M signal and M' idler mode
pairs of which the signal modes are bounced off the beam splitter while the
idler modes are retained losslessly. We obtain a lower bound on the output
state fidelity valid for any pure input state. We define number-diagonal signal
(NDS) states to be input states whose density operator in the signal modes is
diagonal in the multimode number basis. For such input states, we derive series
formulas for the optimal error probability, the output state fidelity, and the
Chernoff-type upper bounds on the error probability. For the special cases of
quantum reading of a classical digital memory and target detection (for which
the reflectivities are real valued), we show that for a given input signal
photon probability distribution, the fidelity is minimized by the NDS states
with that distribution and that for a given average total signal energy N_s,
the fidelity is minimized by any multimode Fock state with N_s total signal
photons. For reading of an ideal memory, it is shown that Fock state inputs
minimize the Chernoff bound. For target detection under high-loss conditions, a
no-go result showing the lack of appreciable quantum advantage over coherent
state transmitters is derived. A comparison of the error probability
performance for quantum reading of number state and two-mode squeezed vacuum
state (or EPR state) transmitters relative to coherent state transmitters is
presented for various values of the reflectances. While the nonclassical states
in general perform better than the coherent state, the quantitative performance
gains differ depending on the values of the reflectances.Comment: 12 pages, 7 figures. This closely approximates the published version.
The major change from v2 is that Section IV has been re-organized, with a
no-go result for target detection under high loss conditions highlighted. The
last sentence of the abstract has been deleted to conform to the arXiv word
limit. Please see the PDF for the full abstrac
Synthesis and Analysis of Entangled Photonic Qubits in Spatial-Parity Space
We present the novel embodiment of a photonic qubit that makes use of one
continuous spatial degree of freedom of a single photon and relies on the the
parity of the photon's transverse spatial distribution. Using optical
spontaneous parametric downconversion to produce photon pairs, we demonstrate
the controlled generation of entangled-photon states in this new space.
Specifically, two Bell states, and a continuum of their superpositions, are
generated by simple manipulation of a classical parameter, the optical-pump
spatial parity, and not by manipulation of the entangled photons themselves. An
interferometric device, isomorphic in action to a polarizing beam splitter,
projects the spatial-parity states onto an even--odd basis. This new physical
realization of photonic qubits could be used as a foundation for future
experiments in quantum information processing.Comment: 6 pages, 5 figures, submitted to PR
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