5,647 research outputs found
Combination of a magnetic Feshbach resonance and an optical bound-to-bound transition
We use laser light near resonant with an optical bound-to-bound transition to
shift the magnetic field at which a Feshbach resonance occurs. We operate in a
regime of large detuning and large laser intensity. This reduces the
light-induced atom-loss rate by one order of magnitude compared to our previous
experiments [D.M. Bauer et al. Nature Phys. 5, 339 (2009)]. The experiments are
performed in an optical lattice and include high-resolution spectroscopy of
excited molecular states, reported here. In addition, we give a detailed
account of a theoretical model that describes our experimental data
Effect of Pauli repulsion and transfer on fusion
The effect of the Pauli exclusion principle on the nucleus-nucleus bare
potential is studied using a new density-constrained extension of the
Frozen-Hartree-Fock (DCFHF) technique. The resulting potentials exhibit a
repulsion at short distance. The charge product dependence of this Pauli
repulsion is investigated. Dynamical effects are then included in the potential
with the density-constrained time-dependent Hartree-Fock (DCTDHF) method. In
particular, isovector contributions to this potential are used to investigate
the role of transfer on fusion, resulting in a lowering of the inner part of
the potential for systems with positive Q-value transfer channels.Comment: Proceedings of an invited talk given at FUSION17, Hobart, Tasmania,
AU (20-24 February, 2017
Remote Entanglement between a Single Atom and a Bose-Einstein Condensate
Entanglement between stationary systems at remote locations is a key resource
for quantum networks. We report on the experimental generation of remote
entanglement between a single atom inside an optical cavity and a Bose-Einstein
condensate (BEC). To produce this, a single photon is created in the
atom-cavity system, thereby generating atom-photon entanglement. The photon is
transported to the BEC and converted into a collective excitation in the BEC,
thus establishing matter-matter entanglement. After a variable delay, this
entanglement is converted into photon-photon entanglement. The matter-matter
entanglement lifetime of 100 s exceeds the photon duration by two orders
of magnitude. The total fidelity of all concatenated operations is 95%. This
hybrid system opens up promising perspectives in the field of quantum
information
A Planarity Test via Construction Sequences
Optimal linear-time algorithms for testing the planarity of a graph are
well-known for over 35 years. However, these algorithms are quite involved and
recent publications still try to give simpler linear-time tests. We give a
simple reduction from planarity testing to the problem of computing a certain
construction of a 3-connected graph. The approach is different from previous
planarity tests; as key concept, we maintain a planar embedding that is
3-connected at each point in time. The algorithm runs in linear time and
computes a planar embedding if the input graph is planar and a
Kuratowski-subdivision otherwise
A continuous non-linear shadowing model of columnar growth
We propose the first continuous model with long range screening (shadowing)
that described columnar growth in one space dimension, as observed in plasma
sputter deposition. It is based on a new continuous partial derivative equation
with non-linear diffusion and where the shadowing effects apply on all the
different processes.Comment: Fast Track Communicatio
You Are Here:Geolocation by Embedding Maps and Images
We present a novel approach to geolocalising panoramic images on a 2-D
cartographic map based on learning a low dimensional embedded space, which
allows a comparison between an image captured at a location and local
neighbourhoods of the map. The representation is not sufficiently
discriminatory to allow localisation from a single image, but when concatenated
along a route, localisation converges quickly, with over 90% accuracy being
achieved for routes of around 200m in length when using Google Street View and
Open Street Map data. The method generalises a previous fixed semantic feature
based approach and achieves significantly higher localisation accuracy and
faster convergence.Comment: 18 pages, new version accepted for ECCV 2020 (poster), with new
results on publicly available dataset and comparison with implementation of
previously published alternative approac
Near-field and far-field analysis of an azimuthally polarized slow Bloch mode microlaser
We report on the near- and far-field investigation of the slow Bloch modes associated with the G point of the Brillouin zone, for a honeycomb lattice photonic crystal, using near-field scanning optical microscopy (NSOM) and infra-red CCD camera. The array of doughnut-shaped monopolar mode (mode M) inside each unit cell, predicted previously by numerical simulation, is experimentally observed in the near-field by means of a metal-coated NSOM tip. In far-field, we detect the azimuthal polarization of the doughnut laser beam due to destructive and constructive interference of the mode radiating from the surface (mode TEM01*). A divergence of 2° for the laser beam and a mode size of (12.8 ± 1) μm for the slow Bloch mode at the surface of the crystal are also estimated. © 2010 Optical Society of America
Deep Memory Networks for Attitude Identification
We consider the task of identifying attitudes towards a given set of entities
from text. Conventionally, this task is decomposed into two separate subtasks:
target detection that identifies whether each entity is mentioned in the text,
either explicitly or implicitly, and polarity classification that classifies
the exact sentiment towards an identified entity (the target) into positive,
negative, or neutral.
Instead, we show that attitude identification can be solved with an
end-to-end machine learning architecture, in which the two subtasks are
interleaved by a deep memory network. In this way, signals produced in target
detection provide clues for polarity classification, and reversely, the
predicted polarity provides feedback to the identification of targets.
Moreover, the treatments for the set of targets also influence each other --
the learned representations may share the same semantics for some targets but
vary for others. The proposed deep memory network, the AttNet, outperforms
methods that do not consider the interactions between the subtasks or those
among the targets, including conventional machine learning methods and the
state-of-the-art deep learning models.Comment: Accepted to WSDM'1
Synthesis of Single Phase Hg-1223 High Tc Superconducting Films With Multistep Electrolytic Process
We report the multistep electrolytic process for the synthesis of high Tc
single phase HgBa2Ca2Cu3O8+ (Hg-1223) superconducting films. The
process includes : i) deposition of BaCaCu precursor alloy, ii) oxidation of
BaCaCu films, iii) electrolytic intercalation of Hg in precursor BaCaCuO films
and iv) electrochemical oxidation and annealing of Hg-intercalated BaCaCuO
films to convert into Hg1Ba2Ca2Cu3O8+ (Hg-1223). Films were
characterized by thermo-gravimetric analysis (TGA) and differential thermal
analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM).
The electrolytic intercalation of Hg in BaCaCuO precursor is proved to be a
novel alternative to high temperature-high pressure mercuration process. The
films are single phase Hg-1223 with Tc = 121.5 K and Jc = 4.3 x 104 A/cm2.Comment: 17 Pages, 10 Figures. Submitted to Superconductor Science and
Technolog
- …