106 research outputs found
Quantum Nonlocality for a Mixed Entangled Coherent State
Quantum nonlocality is tested for an entangled coherent state, interacting
with a dissipative environment. A pure entangled coherent state violates Bell's
inequality regardless of its coherent amplitude. The higher the initial
nonlocality, the more rapidly quantum nonlocality is lost. The entangled
coherent state can also be investigated in the framework of Hilbert
space. The quantum nonlocality persists longer in Hilbert space.
When it decoheres it is found that the entangled coherent state fails the
nonlocality test, which contrasts with the fact that the decohered entangled
state is always entangled.Comment: 20 pages, 7 figures. To be published in J. Mod. Op
Violation of Bell's inequality using classical measurements and non-linear local operations
We find that Bell's inequality can be significantly violated (up to
Tsirelson's bound) with two-mode entangled coherent states using only homodyne
measurements. This requires Kerr nonlinear interactions for local operations on
the entangled coherent states. Our example is a demonstration of
Bell-inequality violations using classical measurements. We conclude that
entangled coherent states with coherent amplitudes as small as 0.842 are
sufficient to produce such violations.Comment: 6 pages, 5 figures, to be published in Phys. Rev.
Laser Tag - An Application of Infrared Communication
The purpose of this project is to design, build, and test laser tag system from the ground up. Much of the laser tag equipment that is available on the market right now use infrared technology to track and register “hits” between players. Our goal is to take this system and redesign it to shoot farther, be more energy efficient, and make it cheaper to produce
Wigner Function Evolution of Quantum States in Presence of Self-Kerr Interaction
A Fokker-Planck equation for the Wigner function evolution in a noisy Kerr
medium ( non-linearity) is presented. We numerically solved this
equation taking a coherent state as an initial condition. The dissipation
effects are discussed. We provide examples of quantum interference, sub-Planck
phase space structures, and Gaussian versus non-Gaussian dynamical evolution of
the state. The results also apply to the description of a nanomechanical
resonator with an intrinsic Duffing nonlinearity.Comment: 10 pages, 11 figure
Quantum entanglement and Bell violation of two coupled cavity fields in dissipative environment
We study the quantum entanglement between two coupled cavities, in which one
is initially prepared in a mesoscopic superposition state and the other is in
the vacuum in dissipative environment and show how the entanglement between two
cavities can arise in the dissipative environment. The dynamic behavior of the
nonlocality for the system is also investigated.Comment: 12 pages, 5 figure
Dynamics of Nonlocality for A Two-Mode Squeezed State in Thermal Environment
We investigate the time evolution of nonlocality for a two-mode squeezed
state in the thermal environment. The initial two-mode pure squeezed state is
nonlocal with a stronger nonlocality for a larger degree of squeezing. It is
found that the larger the degree of initial squeezing is, the more rapidly the
squeezed state loses its nonlocality. We explain this by the rapid destruction
of quantum coherence for the strongly squeezed state.Comment: 5 pages, 3 figures, accepted to PR
Mass Determination and Detection of the Onset of Chromospheric Activity for the Sub-Stellar Object in EF Eridani
EF Eri is a magnetic cataclysmic variable that has been in a low accretion
state for the past nine years. Low state optical spectra reveal the underlying
Zeeman-split white dwarf absorption lines. These features are used to determine
a value of 13-14 MG as the white dwarf field strength. Recently, 5-7 years into
the low state, Balmer and other emission lines have appeared in the optical. An
analysis of the H emission line yields the first radial velocity
solution for EF Eri, leading to a spectroscopic ephemeris for the binary and,
using the best available white dwarf mass of 0.6M, a mass estimate for
the secondary of 0.055M. For a white dwarf mass of 0.95M, the
average for magnetic white dwarfs, the secondary mass increases to
0.087M. At EF Eri's orbital period of 81 minutes, this higher mass
secondary could not be a normal star and still fit within the Roche lobe. The
source of the Balmer and other emission lines is confirmed to be from the
sub-stellar secondary and we argue that it is due to stellar activity. We
compare EF Eri's emission line spectrum and activity behavior to that recently
observed in AM Her and VV Pup and attributed to stellar activity. We explore
observations and models originally developed for V471 Tau, for the RS CVn
binaries, and for extra-solar planets. We conclude that irradiation of the
secondary in EF Eri and similar systems is unlikely and, in polars, the
magnetic field interaction between the two stars (with a possible tidal
component) is a probable mechanism which would concentrate chromospheric
activity on the secondary near the sub-stellar point of the white dwarf.Comment: 49 pages, 12 figures Accepted to ApJ (Main journal
MULTIDISCIPLINARY COLLABORATION AMONG YOUNG SPECIALISTS: RESULTS OF AN ONGOING INTERNATIONAL SURVEY BY YOUNG ORGANISATIONS
Congress of the European-League-Against-Rheumatism (EULAR) (2018, Amsterdam, Netherlands
- …