Quantum memory and non-demolition measurement of single phonon state with nitrogen-vacancy centers ensemble

In diamond, the mechanical vibration induced strain can lead to interaction between the mechanical mode and the nitrogen-vecancy (NV) centers. In this work, we propose to utilize the strain induced coupling for the quantum non-demolition (QND) single phonon measurement and memory in diamond. The single phonon in a diamond mechanical resonator can be perfectly absorbed and emitted by the NV centers ensemble (NVE) with adiabatically tuning the microwave driving. An optical laser drives the NVE to the excited states, which have much larger coupling strength to the mechanical mode. By adiabatically eliminating the excited states under large detuning limit, the effective coupling between the mechanical mode and the NVE can be used for QND measurement of the single phonon state. Under realistic experimental conditions, we numerically simulate the scheme. It is found that the fidelity of the absorbing and emitting process can reach a much high value. The overlap between the input and the output phonon shapes can reach $98.57\%$.Comment: 7 pages, 3 figure

Governance Mechanism of E-health in Chinese Urban Communities: The Case of Zhabei District in Shanghai

E-health governance can be divided into four kinds of models: government-oriented, market-oriented, government-market cooperation, and multi-collaborative governance. With the development of market economy, democratic consciousness and management philosophy, traditional e-health management faces many challenges. And multi-collaborative governance model is becoming a good choice for the community e-health. In order to further analyze the characteristics and applicability of this model and explore the sustainable development path, this paper selects Zhabei District as a typical case and distinguishes the roles of different governance bodies in community e-health. By this study, we recognize that the e-health governance of Chinese urban community has some problems, such as, insufficient involvement of non-governmental body, obvious conflict of interest and the lack of collaboration among the various subjects. Therefore, it is supposed to construct an integrated e-health development mechanism. Based on collaborative governance theory, the mechanism has to follow three basic principles. At the same time, effective operation of this mechanism need five mechanisms which include trust, communication and negotiation, cost sharing, supervision and feedback. Key words: community e-health, collaborative governance, medical service, Zhabei Distric

Design and fabrication of robust broadband extreme ultraviolet multilayers

The random layer thickness variations can induce a great deformation of the experimental reflection of broadband extreme ultraviolet multilayer. In order to reduce this influence of random layer thickness fluctuations, the multiobjective genetic algorithm has been improved and used in the robust design of multilayer with a broad angular bandpass. The robust multilayer with a lower sensitivity to random thickness errors have been obtained and the corresponding multilayer mirrors were fabricated. The experimental results of robust Mo/Si multilayer with a wide angular band were presented and analyzed, and the advantage of robust multilayer design was demonstrated

Constitutive equation for the hot deformation behavior of Csf/AZ91D composites and its validity for numerical simulation

The flow stress behavior of 10 vol. % short carbon fibers reinforced AZ91D composites (C-sf/AZ91D) were investigated by hot compression test. The results show the flow stress reach the peak value at small strain and then decrease monotonically until the end of the large strain, which exhibits an obvious dynamic strain softening. The decrease of stress level with deformation temperature increasing or strain rate decreasing can be represented by Zener-Hollomon parameter in a hyperbolic sine equation. By considering the effect of strain on material constants, a modified viscoplastic constitutive equation was established to characterize the dependence of flow stress on the deformation temperature, strain, and strain rate. The stress-strain values calculated by the constitutive equation are in consistent with the experimental results. Applying the constitutive equation, the plastic deformation of C-sf/AZ91D) composites during the hot compression process were analyzed by finite element simulation. The calculated punch force-stroke curves agree well with the measured ones. The results confirmed that the established constitutive equation can accurately describe the hot plastic deformation behavior of C-sf/AZ91D composites, and can be used for the finite element analysis on the hot forming process. (C) 2016 Elsevier Ltd. All rights reserved

Bis(2-amino­benzothia­zol-3-ium) bis­(7-oxabicyclo­[2.2.1]heptane-2,3-dicarboxyl­ato-κ3 O 2,O 3,O 7)nickelate(II) hexa­hydrate

In the title compound, (C7H7N2S)2[Ni(C8H8O5)2]·6H2O, the NiII cation is located on an inversion center and is O,O′,O′′-chelated by two symmetry-related 7-oxabicyclo­[2.2.1]heptane-2,3-dicarboxyl­ate anions in a distorted octa­hedral geometry. The 2-amino­benzothia­zol-3-ium cation links with the Ni complex anion via N—H⋯O hydrogen bonding. Extensive O—H⋯O and N—H⋯O hydrogen bonds involving the lattice water mol­ecules also occur in the crystal structure

Tunable strong plasmon-exciton coupling based on borophene and deep subwavelength perovskite grating

Two-dimensional materials support deeply confined and tunable plasmonic modes, which have great potential for achieving device miniaturization and flexible manipulation. In this paper, we propose a diffraction-unlimited system composed of borophene layer and perovskite grating to investigate the strong coupling between the borophene guiding plasmon (BGP) and perovskite exciton (PE) mode. The resonant energy of BGP mode could be electrically tuned to match the energy of PE mode, and a remarkable Rabi splitting is attained under zero-detuning condition. The splitting energy could reach 230 meV due to the strong field enhancement provided by BGP mode. Consequently, an active reflective phase modulation with 1.76{\pi} range is achieved by dynamically manipulating the detuning. Furthermore, by increasing the distance between the borophene layer and perovskite grating, a parity-time symmetry breaking could be observed with the vanished energy splitting. Our results deepen the understanding of light-matter interaction at the sub-wavelength scale and provide a guideline for designing active plasmonic devices.Comment: 9 pages, 4 figure