Separable and entangled states in the high-spin XX central spin model

It is shown in a recent preprint [arXiv:2001.10008] that the central spin model with XX-type qubit-bath coupling is integrable for a central spin $s_0=1/2$. Two types of eigenstates, separable states (dark states) and entangled states (bright states) between the central spin and the bath spins, are manifested. In this work, we show by using an operator product state approach that the XX central spin model with central spin $s_0>1/2$ and inhomogeneous coupling is partially solvable. That is, a subset of the eigenstates are obtained by the operator product state ansatz. These are the separable states and those entangled states in the single-spin-excitation subspace with respect to the fully polarized reference state. Due to the high degeneracy of the separable states, the resulting Bethe ansatz equations are found to be non-unique. In the case of $s_0=1/2$ we show that all the separable and entangled states can be written in terms of the operator product states, recovering the results in [arXiv:2001.10008]. Moreover, we also apply our method to the case of homogeneous coupling and derive the corresponding Bethe ansatz equations.Comment: 12 pages, 2 figures, to appear in Physical Review

Noise suppression of on-chip mechanical resonators by chaotic coherent feedback

We propose a method to decouple the nanomechanical resonator in optomechanical systems from the environmental noise by introducing a chaotic coherent feedback loop. We find that the chaotic controller in the feedback loop can modulate the dynamics of the controlled optomechanical system and induce a broadband response of the mechanical mode. This broadband response of the mechanical mode will cut off the coupling between the mechanical mode and the environment and thus suppress the environmental noise of the mechanical modes. As an application, we use the protected optomechanical system to act as a quantum memory. It's shown that the noise-decoupled optomechanical quantum memory is efficient for storing information transferred from coherent or squeezed light

(3-{[N-(5-Chloro-2-hy­droxy­phen­yl)oxamo­yl]amino}­prop­yl)dimethyl­aza­nium perchlorate

In the title compound, C13H19ClN3O3 +·ClO4 −, the 3-(di­meth­yl­ammonio)­propyl group of the cation is disordered over two sets of sites with occupancies 0.772 (6) and 0.228 (6). The cations are joined by pairs of N—H⋯O hydrogen bonds into centrosymmetric dimers and these dimers are assembled into chains along the a-axis direction, also through N—H⋯O hydrogen bonds. The perchlorate anions are linked to the hy­droxy groups of the cations by O—H⋯O hydrogen bonds. The positively charged ammonium groups and the anions give rise to folded layers parallel to the ab plane

Administration of a novel penicillamine-bound membrane: a preventive and therapeutic treatment for abdominal adhesions

<p>Abstract</p> <p>Background</p> <p>Adhesions formation is a significant postsurgical complication. At present, there is no effective method for preventing adhesions formation <abbrgrp><abbr bid="B1">1</abbr></abbrgrp>, although barrier products such as Dextran (Dex) <abbrgrp><abbr bid="B2">2</abbr></abbrgrp> and sodium hyaluronate (SH) <abbrgrp><abbr bid="B3">3</abbr></abbrgrp> have proved the most clinically successful <abbrgrp><abbr bid="B4">4</abbr><abbr bid="B5">5</abbr><abbr bid="B6">6</abbr></abbrgrp>, This study is designed to investigate the preventive and therapeutic potential of a novel penicillamine-bound membrane for abdominal adhesions formation.</p> <p>Methods</p> <p>150 rats were involved in the present study. All animals were randomly divided into 6 groups (1 vehicle group and 5 test groups respectively treated with dextran, sodium hyaluronate, penicillamine, penicillamine-bound membrane or non-penicillamine-bound membrane). The occurrence, grade and score of abdominal adhesions were compared between the different groups. The breaking strength of incision was compared between the vehicle group and the penicillamine, membrane with/without penicillamine - treated groups. Expression of collagen type I was compared between the vehicle and penicillamine-treated group. The occurrence of adhesions was compared between the Dextran (Dex), sodium hyaluronate (SH), penicillamine-treated group and membrane with or without penicillamine- treated groups.</p> <p>Results</p> <p>Penicillamine and penicillamine-bound membrane had significant preventive effects on abdominal adhesions formation, better than dextran, sodium hyaluronate and non-penicillamine-bound membrane. However, neither of them influenced incision healing, although they insignificantly decreased the breaking strength of the incision. Penicillamine-bound membrane, which can be loaded locally and more efficaciously, shows greater advantages than penicillamine.</p> <p>Conclusions</p> <p>Penicillamine-bound membrane can be applied as an effective therapeutic intervention for abdominal adhesions with inconsequential side effects.</p

A novel measurement of Bs0B^0_s and Ds−D^-_s lifetimes using semileptonic decays at LHCb

I report new, world-leading LHCb results on heavy meson lifetimes. We use a novel approach that suppresses the shortcomings typically associated with reconstruction of semileptonic decays, allowing for precise measurements of lifetimes and other properties in collider experiments. We achieve a 15% and a $2\times$ improvement over current best determinations of the flavor-specific $B^0_s$ lifetime and $D^-_s$ lifetime, respectively.Comment: 12 pages, 6 figures. Talk presented at the APS Division of Particles and Fields Meeting (DPF 2017), July 31-August 4, 2017, Fermilab. C17073