45,879 research outputs found
Observation of sub-Poisson photon statistics in the cavity-QED microlaser
We have measured the second-order correlation function of the cavity-QED
microlaser output and observed a transition from photon bunching to
antibunching with increasing average number of intracavity atoms. The observed
correlation times and the transition from super- to sub-Poisson photon
statistics can be well described by gain-loss feedback or enhanced/reduced
restoring action against fluctuations in photon number in the context of a
quantum microlaser theory and a photon rate equation picture. However, the
theory predicts a degree of antibunching several times larger than that
observed, which may indicate the inadequacy of its treatment of atomic velocity
distributions.Comment: 4 pages, 4 figure
Constraining the Skyrme effective interactions and the neutron skin thickness of nuclei using isospin diffusion data from heavy ion collisions
Recent analysis of the isospin diffusion data from heavy-ion collisions based
on an isospin- and momentum-dependent transport model with in-medium
nucleon-nucleon cross sections has led to the extraction of a value of MeV for the slope of the nuclear symmetry energy at saturation density.
This imposes stringent constraints on both the parameters in the Skyrme
effective interactions and the neutron skin thickness of heavy nuclei. Among
the 21 sets of Skyrme interactions commonly used in nuclear structure studies,
the 4 sets SIV, SV, G, and R are found to give values
that are consistent with the extracted one. Further study on the correlations
between the thickness of the neutron skin in finite nuclei and the nuclear
matter symmetry energy in the Skyrme Hartree-Fock approach leads to predicted
thickness of the neutron skin of fm for Pb, fm for Sn, and fm for Sn.Comment: 10 pages, 4 figures, 1 Table, Talk given at 1) International
Conference on Nuclear Structure Physics, Shanghai, 12-17 June, 2006; 2) 11th
China National Nuclear Structure Physics Conference, Changchun, Jilin, 13-18
July, 200
Deep Reinforcement Learning for Quantum Gate Control
How to implement multi-qubit gates efficiently with high precision is
essential for realizing universal fault tolerant computing. For a physical
system with some external controllable parameters, it is a great challenge to
control the time dependence of these parameters to achieve a target multi-qubit
gate efficiently and precisely. Here we construct a dueling double deep
Q-learning neural network (DDDQN) to find out the optimized time dependence of
controllable parameters to implement two typical quantum gates: a single-qubit
Hadamard gate and a two-qubit CNOT gate. Compared with traditional optimal
control methods, this deep reinforcement learning method can realize efficient
and precise gate control without requiring any gradient information during the
learning process. This work attempts to pave the way to investigate more
quantum control problems with deep reinforcement learning techniques.Comment: 7 pages, 6 figure
Sumoylation silences the plasma membrane leak K+ channel K2P1.
Reversible, covalent modification with small ubiquitin-related modifier proteins (SUMOs) is known to mediate nuclear import/export and activity of transcription factors. Here, the SUMO pathway is shown to operate at the plasma membrane to control ion channel function. SUMO-conjugating enzyme is seen to be resident in plasma membrane, to assemble with K2P1, and to modify K2P1 lysine 274. K2P1 had not previously shown function despite mRNA expression in heart, brain, and kidney and sequence features like other two-P loop K+ leak (K2P) pores that control activity of excitable cells. Removal of the peptide adduct by SUMO protease reveals K2P1 to be a K+-selective, pH-sensitive, openly rectifying channel regulated by reversible peptide linkage
Structure And Properties of Nanoparticles Formed under Conditions of Wire Electrical Explosion
Structure and properties of nanoparticles formed under conditions of wire
electrical explosion were studied. It was shown that the state of WEE power
particles can be characterized as a metastable state. It leads to an increased
stability of nanopowders at normal temperatures and an increased reactivity
during heating, which is revealed in the form of threshold phenomena.Comment: Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions
The future design direction of smart clothing development
Literature indicates that Smart Clothing applications, the next generation of clothing and
electronic products, have been struggling to enter the mass market because the consumers’
latent needs have not been recognised. Moreover, the design direction of Smart Clothes
remains unclear and unfocused. Nevertheless, a clear design direction is necessary for all
product development. Therefore, this research aims to identify the design directions of the
emerging Smart Clothes industry by conducting a questionnaire survey and focus groups
with its major design contributors. The results reveal that the current strategy of embedding
a wide range of electronic functions in a garment is not suitable. This is primarily because it
does not match the users’ requirements, purchasing criteria and lifestyle. The results
highlight the respondents’ preference for personal healthcare and sportswear applications
that suit their lifestyle, are aesthetically attractive, and provide a practical function
Strong decays of in an extended chiral quark model
The strong decays of the resonance are investigated in an
extended chiral quark model by including the low-lying components
in addition to the component. The results show that these five-quark
components in contribute significantly to the and decays. The contributions to the decay
come from both the lowest energy and the next-to-lowest energy five-quarks
components, while the contributions to the decay come from only the
latter one. Taking these contributions into account, the description for the
strong decays of is improved, especially, for the puzzling large
ratio of the decays to and .Comment: 6 pages, 1 figur
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