8,069 research outputs found
Experimental Bell Inequality Violation with an Atom and a Photon
We report the measurement of a Bell inequality violation with a single atom
and a single photon prepared in a probabilistic entangled state. This is the
first demonstration of such a violation with particles of different species.
The entanglement characterization of this hybrid system may also be useful in
quantum information applications.Comment: 4 pages, 2 figure
Efficient fluorescence collection from trapped ions with an integrated spherical mirror
Efficient collection of fluorescence from trapped ions is crucial for quantum
optics and quantum computing applications, specifically, for qubit state
detection and in generating single photons for ion-photon and remote ion
entanglement. In a typical setup, only a few per cent of ion fluorescence is
intercepted by the aperture of the imaging optics. We employ a simple metallic
spherical mirror integrated with a linear Paul ion trap to achieve photon
collection efficiency of at least 10% from a single Ba ion. An aspheric
corrector is used to reduce the aberrations caused by the mirror and achieve
high image quality.Comment: 5 pages and 4 figure
Polarity-dependent dielectric torque in nematic liquid crystals
The dielectric dispersion in the uniaxial nematic liquid crystals affects the
switching dynamics of the director, as the dielectric torque is determined by
not only the present values of the electric field and director but also by
their past values. We demonstrate that this dielectric memory leads to an
unusual contribution to the dielectric torque that is linear in the present
field and thus polarity-sensitive. This torque can be used to accelerate the
switch-off phase of director dynamics.Comment: 12 pages, 4 figure
Zero-Point cooling and low heating of trapped 111Cd+ ions
We report on ground state laser cooling of single 111Cd+ ions confined in
radio-frequency (Paul) traps. Heating rates of trapped ion motion are measured
for two different trapping geometries and electrode materials, where no effort
was made to shield the electrodes from the atomic Cd source. The low measured
heating rates suggest that trapped 111Cd+ ions may be well-suited for
experiments involving quantum control of atomic motion, including applications
in quantum information science.Comment: 4 pages, 6 figures, Submitted to PR
Molecular machines or pleiomorphic ensembles: signaling complexes revisited
Signaling complexes typically consist of highly dynamic molecular ensembles that are challenging to study and to describe accurately. Conventional mechanical descriptions misrepresent this reality and can be actively counterproductive by misdirecting us away from investigating critical issues
Temporal response to harmonic driving in electroconvection
The temporal evolution of the spatially periodic electroconvection (EC)
patterns has been studied within the period of the driving ac voltage by
monitoring the light intensity diffracted from the pattern. Measurements have
been carried out on a variety of nematic systems, including those with negative
dielectric and positive conductivity anisotropy, exhibiting "standard EC"
(s-EC), those with both anisotropies negative exhibiting "non-standard EC"
(ns-EC), as well as those with the two anisotropies positive. Theoretical
predictions have been confirmed for stationary s-EC and ns-EC patterns.
Transitions with Hopf bifurcation have also been studied. While traveling had
no effect on the temporal evolution of dielectric s-EC, traveling conductive
s-EC and ns-EC patterns exhibited a substantially altered temporal behavior
with a dependence on the Hopf frequency. It has also been shown that in
nematics with both anisotropies positive, the pattern develops and decays
within an interval much shorter than the period, even at relatively large
driving frequencies.Comment: 19 pages, 5 figure
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