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排序方式: 共有437条查询结果,搜索用时 31 毫秒
31.
We theoretically investigate cavity-linewidth narrowing by means of voltage-controlled induced transparency in asymmetric double quantum dot system. The impact of voltage on frequency pulling and cavity linewidth narrowing is discussed. The linewidth and position of the cavity transmission can be engineered by the bias voltage. The scheme may be useful in designing novel optoelectronic devices. 相似文献
32.
We propose schemes to prepare atomic entangled states in a bi-mode cavity via stimulated Raman adiabatic passage (STIRAP) and fractional stimulated Raman adiabatic passage (f-STIRAP) techniques. Our scheme should be realizable in the near future because of the existence of all experimental ingredients. Our numerical simulation shows we can entangle the atoms with high fidelities by choosing proper laser pulses. 相似文献
33.
A.R. Bosco de Magalhães 《Physics letters. A》2011,375(46):4120-4129
The relation between microscopic symmetries in the system-environment interaction and the emergence of robust states is studied for many linearly coupled harmonic oscillators. Different types of symmetry, which are introduced into the model as terms in the coupling constants between each system?s oscillator and a common reservoir, lead to distinct robust modes. Since these modes are partially or completely immune to the symmetric part of the environmental noise, they are good candidates for building quantum memories. A comparison of the model investigated here, with bilinear system-reservoir coupling, and a model where such coupling presents an exponential dependence on the variables of interest is performed. 相似文献
34.
In this paper, we report 30 THz measurements of ammonia in its excited, ν2 = 1, inversion state. These measurements include transition frequencies and pressure shifts (where significant enough to be observed). Included in the data are two forbidden and three ro-inversion transitions, as well as 18 transitions never directly measured before. The measurements were made with an all-solid-state, diode-laser, difference-frequency spectrometer. Using an innovative laser-frequency locking scheme, this spectrometer provided accurately determined and continuously tuned THz-frequencies without requiring accurate knowledge of the absolute laser frequencies. The details of the spectrometer’s frequency calibration is discussed. A global analysis of NH3 based on the available ground state, ν2 = 1 state, and ν2-band transitions was carried out, and the resulting set of recommended molecular effective-Hamiltonian parameters for ammonia is presented. In addition, calculated center frequencies and intensities for all possible transitions up to J = 20 between rotation, inversion, and vibration levels in the ground and ν2 = 1 states are included as supplementary material. 相似文献
35.
Microcrystalline solid dysprosium(III) hexacyanoferrate(II) was synthesized by co-precipitation in aqueous solution. The resulting solid has been studied by Fourier transform infrared spectroscopy, X-ray analysis and solid state electrochemistry. The use of a cavity microelectrode was necessary to explore a wide range of time scale and minimize the (undesired) capacitive currents. Cyclic voltametric experiments were very helpful to understand the kinetic of charge transfer in such microstructure. A structure-properties relationship has been established from the crystallographic and the electrochemical properties. A square-scheme is presented to explain the unique electrochemical behavior of hexacyanoferrate containing dysprosium since this compound exhibits a second redox system. The solid presents an open channel-like morphology in which the motion of charged species occurs during the redox processes. Precisely, the electronic transfer is accompanied by a cation diffusion inside the microcrystalline structure. The size of these channels strongly suggests that the kinetic of charge transfer is limited by the cation transport into these structures. 相似文献
36.
《Photonics and Nanostructures》2005,3(2-3):63-74
We discuss recent progress and the exciting potential of scanning probe microscopy methods for the characterization and control of photonic crystals. We demonstrate that scanning near-field optical microscopy can be used to characterize the performance of photonic crystal device components on the sub-wavelength scale. In addition, we propose scanning probe techniques for realizing local, low-loss tuning of photonic crystal resonances, based on the frequency shifts that high-index nanoscopic probes can induce. Finally, we discuss prospects for on-demand spontaneous emission control. We demonstrate theoretically that photonic crystal membranes induce large variations in spontaneous emission rate over length scales of 50 nm that can be probed by single light sources, or nanoscopic ensembles of light sources attached to the end of a scanning probe. 相似文献
37.
38.
一、引言在地震动情况下,地下结构与地面结构相比较其动力响应是十分不同的。以桥梁和水堤为例,对这类结构的设计,水平惯性力是一个极为重要的因素。可是,对于地下结构,以埋管为例,惯性荷载主要由其周围的土介质所承受。地下管道系统的地震破坏, 相似文献
39.
Dmitry O. Krimer Matthias Zens Stefan Putz Stefan Rotter 《Laser \u0026amp; Photonics Reviews》2016,10(6):1023-1030
A very promising recent trend in applied quantum physics is to combine the advantageous features of different quantum systems into what is called “hybrid quantum technology”. One of the key elements in this new field will have to be a quantum memory enabling to store quanta over extended periods of time. Systems that may fulfill the demands of such applications are comb‐shaped spin ensembles coupled to a cavity. Due to the decoherence induced by the inhomogeneous ensemble broadening, the storage time of these quantum memories is, however, still rather limited. Here we demonstrate how to overcome this problem by burning well‐placed holes into the spectral spin density leading to spectacular performance in the multimode regime. Specifically, we show how an initial excitation of the ensemble leads to the emission of more than a hundred well‐separated photon pulses with a decay rate significantly below the fundamental limit of the recently proposed “cavity protection effect”.
40.
This paper focuses on an experimental investigation of different types of insulated hollow-brick cavity walls, i.e., walls
with a door opening, with a window opening and without any opening, characterized with different tie bar arrangements, subjected
to slowly applied cyclic loads. The cracking and damage patterns, strength and stiffness degradation and deterioration, energy
dissipation capacity and hysteretic feature are analyzed. Based on the experimental results, the formulae of calculation for
the cracking load and the ultimate load of cavity wall are mathematically established. The evaluation equation of strength
and stiffness degradation of walls is presented and its parameters are numerically given from regression results. The original
characteristic curves of recovery force-displacement of actual specimens under cyclic loads are discussed, and then a standard
recovery force-displacement model is suggested with convenient forms for implementation. 相似文献