18,515 research outputs found
Zero-field and Larmor spinor precessions in a neutron polarimeter experiment
We present a neutron polarimetric experiment where two kinds of spinor
precessions are observed: one is induced by different total energy of neutrons
(zero-field precession) and the other is induced by a stationary guide field
(Larmor precession). A characteristic of the former is the dependence of the
energy-difference, which is in practice tuned by the frequency of the
interacting oscillating magnetic field. In contrast the latter completely
depends on the strength of the guide field, namely Larmor frequency. Our
neutron-polarimetric experiment exhibits individual tuning as well as specific
properties of each spinor precession, which assures the use of both spin
precessions for multi-entangled spinor manipulation.Comment: 12 pages, 4 figure
Noncyclic Pancharatnam phase for mixed state SU(2) evolution in neutron polarimetry
We have measured the Pancharatnam relative phase for spin-1/2 states. In a
neutron polarimetry experiment the minima and maxima of intensity modulations,
giving the Pancharatnam phase, were determined. We have also considered general
SU(2) evolution for mixed states. The results are in good agreement with
theory.Comment: 5 pages, 4 figures, to be published in Phys.Lett.
Superconductivity of Quasi-One-Dimensional Electrons in Strong Magnetic Field
The superconductivity of quasi-one-dimensional electrons in the magnetic
field is studied. The system is described as the one-dimensional electrons with
no frustration due to the magnetic field. The interaction is assumed to be
attractive between electrons in the nearest chains, which corresponds to the
lines of nodes of the energy gap in the absence of the magnetic field. The
effective interaction depends on the magnetic field and the transverse
momentum. As the magnetic field becomes strong, the transition temperature of
the spin-triplet superconductivity oscillates, while that of the spin-singlet
increases monotonically.Comment: 15 pages, RevTeX, 3 PostScript figures in uuencoded compressed tar
file are appende
Violation of Bell-like Inequality for spin-energy entanglement in neutron polarimetry
Violation of a Bell-like inequality for a spin-energy entangled neutron state
has been confirmed in a polarimetric experiment. The proposed inequality, in
Clauser-Horne-Shimony-Holt (CHSH) formalism, relies on correlations between the
spin and energy degree of freedom in a single-neutron system. The entangled
states are generated utilizing a suitable combination of two radio-frequency
fields in a neutron polarimeter setup. The correlation function S is determined
to be 2.333+/-0.005, which violates the Bell-like CHSH inequality by more than
66 standard deviations.Comment: 4 pages 2 figure
A Comparative Study of Infrared Asteroid Surveys: IRAS, AKARI, and WISE
We present a comparative study of three infrared asteroid surveys based on
the size and albedo data from the Infrared Astronomical Satellite (IRAS), the
Japanese infrared satellite AKARI, and the Wide-field Infrared Survey Explorer
(WISE). Our study showed that: (i) the total number of asteroids detected with
diameter and albedo information with these three surveyors is 138,285, which is
largely contributed by WISE; (ii) the diameters and albedos measured by the
three surveyors for 1,993 commonly detected asteroids are in good agreement,
and within +/-10% in diameter and +/-22% in albedo at 1sigma deviation level.
It is true that WISE offers size and albedo of a large fraction (>20%) of known
asteroids down to a few km bodies, but we would suggest that the IRAS and AKARI
catalogs compensate for larger asteroids up to several hundred km, especially
in the main belt region. We discuss the complementarity of these three catalogs
in order to facilitate the use of these data sets for characterizing the
physical properties of minor planets.Comment: 21 pages, 19 figures, and 2 tables, accepted for publication in PAS
Assessing Public Priorities for Police Oversight in King County
Over the last century, police oversight offices emerged to address police misconduct and promote public confidence, including four oversight offices within King County. Although oversight offices are intended to represent the interests of the public, they rarely or irregularly solicit public opinion. An online survey was developed to answer the general research question, âWhat are the publicâs priorities for police oversight in King County?â and it appears to be the first attitudinal survey of its kind in the United States. A total of 1,700 survey responses were recorded, of which 1,110 were completed with 60% or higher item response by King Countybased respondents. Results reveal that the issues of most importance to the public of King County are: ensuring the public receives timely, accurate updates about a case following a deadly force incident (52%); tracking trends in police use of force (52%); providing general support and guidance to families following a use-of-force incident (47%); and monitoring the development and implementation of police training curricula (47%). An overwhelming majority of respondents believe that the use of dash or body cameras will improve the quality of policing and police accountability (74%). The study also gauged public experiences with oversight. Statistical testing confirms significant relationships between experience with oversight and gender, race, age, political identity, and having familial ties to law enforcement
Quantum Hall Effect in Three-dimensional Field-Induced Spin Density Wave Phases with a Tilted Magnetic Field
The quantum Hall effect in the three-dimensional anisotropic tight-binding
electrons is investigated in the field-induced spin density wave phases with a
magnetic field tilted to any direction. The Hall conductivity,
and , are shown to be quantized as a function of the wave vector
of FISDW, while stays zero, where is the most conducting
direction and and are perpendicular to .Comment: 18 pages, REVTeX 3.0, 1 figure is available upon request, to be
published in Physical Review
Fermionic bright soliton in a boson-fermion mixture
We use a time-dependent dynamical mean-field-hydrodynamic model to study the
formation of fermionic bright solitons in a trapped degenerate Fermi gas mixed
with a Bose-Einstein condensate in a quasi-one-dimensional cigar-shaped
geometry. Due to a strong Pauli-blocking repulsion among spin-polarized
fermions at short distances there cannot be bright fermionic solitons in the
case of repulsive boson-fermion interactions. However, we demonstrate that
stable bright fermionic solitons can be formed for a sufficiently attractive
boson-fermion interaction in a boson-fermion mixture. We also consider the
formation of fermionic solitons in the presence of a periodic axial
optical-lattice potential. These solitons can be formed and studied in the
laboratory with present technology.Comment: 7 pages, 7 ps figure
Towards a relativistic statistical theory
In special relativity the mathematical expressions, defining physical
observables as the momentum, the energy etc, emerge as one parameter (light
speed) continuous deformations of the corresponding ones of the classical
physics. Here, we show that the special relativity imposes a proper one
parameter continuous deformation also to the expression of the classical
Boltzmann-Gibbs-Shannon entropy. The obtained relativistic entropy permits to
construct a coherent and selfconsistent relativistic statistical theory [Phys.
Rev. E {\bf 66}, 056125 (2002); Phys. Rev. E {\bf 72}, 036108 (2005)],
preserving the main features (maximum entropy principle, thermodynamic
stability, Lesche stability, continuity, symmetry, expansivity, decisivity,
etc.) of the classical statistical theory, which is recovered in the classical
limit. The predicted distribution function is a one-parameter continuous
deformation of the classical Maxwell-Boltzmann distribution and has a simple
analytic form, showing power law tails in accordance with the experimental
evidence.Comment: Physica A (2006). Proof correction
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