Recently, cavity optomechanics has become a rapidly developing research field exploring the coupling between the optical field and mechanical oscillation. Cavity optomechanical systems were predicted to exhibit rich a...Recently, cavity optomechanics has become a rapidly developing research field exploring the coupling between the optical field and mechanical oscillation. Cavity optomechanical systems were predicted to exhibit rich and nontrivial effects due to the nonlinear optomechanical interaction. However, most progress during the past years have focused on the linearization of the optomechanical interaction, which ignored the intrinsic nonlinear nature of the optomechanical coupling. Exploring nonlinear optomechanical interaction is of growing interest in both classical and quantum mechanisms, and nonlinear optomechanical interaction has emerged as an important new frontier in cavity optomechanics. It enables many applications ranging from single-photon sources to generation of nonclassical states. Here, we give a brief review of these developments and discuss some of the current challenges in this field.展开更多
Up to now, there have been many indistinctive points in the image interpretation of scanning tunnelhng microscopy (STM) system, and the problems have attracted almost all STM scientists’ attention. In 1992, Kenkre pr...Up to now, there have been many indistinctive points in the image interpretation of scanning tunnelhng microscopy (STM) system, and the problems have attracted almost all STM scientists’ attention. In 1992, Kenkre proposed the new programme which describes the behaviour of the electrons moving in the STM tunnelling by the method of exciton dynamics, and the programme not only breaks through the restrictions of Tersoff-Hamann theory, but also can be applied conveniently to discussing the effects of the tip structure, adsorbate structure, substrate structure, temperature, tunneling voltage, and the degree of coherence of elec-展开更多
The Hamiltonian of the quantum rod （QR） with an ellipsoidal boundary is given after a coordinate transformation. Using the linear-combination operator and unitary transformation methods, the vibrational frequency an...The Hamiltonian of the quantum rod （QR） with an ellipsoidal boundary is given after a coordinate transformation. Using the linear-combination operator and unitary transformation methods, the vibrational frequency and the ground-state energy of weak-coupling polarons are obtained. Numerical results illustrate that the vibrational frequency increases with the decrease of the effective radius R0 of the ellipsoidal parabolic potential and the aspect ratio e of the ellipsoid, and that the ground-state energy increases with the decrease of the effective radius R0 and the electron-LO-phonon coupling strength α. In addition, the ground-state energy decreases with increasing aspect ratio e within 0 〈 e 〈 1 and reaches a minimum when e = 1, and then increases with increasing e for e 〉 1.展开更多
We present a weak-coupling theory of semiclassical periodically driven two-level systems. The explicit analytical approximating solution is shown to reproduce highly accurately the exact results well beyond the regime...We present a weak-coupling theory of semiclassical periodically driven two-level systems. The explicit analytical approximating solution is shown to reproduce highly accurately the exact results well beyond the regime of the rotating-wave approximation.展开更多
The magnetically coupled resonant wireless power transfer(MCR-WPT)system for implantable medical devices has gradually become one of the research hotspots.The transmission characteristics of the system in weak-couplin...The magnetically coupled resonant wireless power transfer(MCR-WPT)system for implantable medical devices has gradually become one of the research hotspots.The transmission characteristics of the system in weak-coupling regions are of research significance.The mathematical model of the system's transmission characteristics is established by equivalent circuit theory.Several key factors that affect the transmission characteristics of the system are obtained,to include the self-inductance of the coil,the mutual inductance between the coils,and the load resistance.A magnetically coupled resonant wireless power transfer system is designed.A method of coil design is proposed.The transmission efficiency of the system in the weak-coupling region is improved by optimizing the design of the coil.Simulation and experimental results exhibited good consistency.The results show that the transmission performance of the system in the weak-coupling area is improved.This work provides guidance and practical significance for the research of the MCR-WPT system with implantable medical equipment.展开更多
基金supported by the National Natural Fundamental Research Program of China(Grant No.2012CB922103)the National Science Foundation of China(Grant Nos.11375067,11275074,11374116,11204096 and 11405061)the Fundamental Research Funds for the Central Universities HUST(Grant No.2014QN193)
文摘Recently, cavity optomechanics has become a rapidly developing research field exploring the coupling between the optical field and mechanical oscillation. Cavity optomechanical systems were predicted to exhibit rich and nontrivial effects due to the nonlinear optomechanical interaction. However, most progress during the past years have focused on the linearization of the optomechanical interaction, which ignored the intrinsic nonlinear nature of the optomechanical coupling. Exploring nonlinear optomechanical interaction is of growing interest in both classical and quantum mechanisms, and nonlinear optomechanical interaction has emerged as an important new frontier in cavity optomechanics. It enables many applications ranging from single-photon sources to generation of nonclassical states. Here, we give a brief review of these developments and discuss some of the current challenges in this field.
文摘Up to now, there have been many indistinctive points in the image interpretation of scanning tunnelhng microscopy (STM) system, and the problems have attracted almost all STM scientists’ attention. In 1992, Kenkre proposed the new programme which describes the behaviour of the electrons moving in the STM tunnelling by the method of exciton dynamics, and the programme not only breaks through the restrictions of Tersoff-Hamann theory, but also can be applied conveniently to discussing the effects of the tip structure, adsorbate structure, substrate structure, temperature, tunneling voltage, and the degree of coherence of elec-
基金supported by the National Natural Science Foundation of China (No. 10347004)the Science Research for the Colleges and Universities of Inner Mongolia Autonomous Region (No. NJzy08085)
文摘The Hamiltonian of the quantum rod （QR） with an ellipsoidal boundary is given after a coordinate transformation. Using the linear-combination operator and unitary transformation methods, the vibrational frequency and the ground-state energy of weak-coupling polarons are obtained. Numerical results illustrate that the vibrational frequency increases with the decrease of the effective radius R0 of the ellipsoidal parabolic potential and the aspect ratio e of the ellipsoid, and that the ground-state energy increases with the decrease of the effective radius R0 and the electron-LO-phonon coupling strength α. In addition, the ground-state energy decreases with increasing aspect ratio e within 0 〈 e 〈 1 and reaches a minimum when e = 1, and then increases with increasing e for e 〉 1.
基金The project supported by National Natural Science Foundation of China under Grant Nos. 10575040, 90503010, 60478029, and 10634060, and by the State Key Basic Research Program under Grant No. 2005CB724508
文摘We present a weak-coupling theory of semiclassical periodically driven two-level systems. The explicit analytical approximating solution is shown to reproduce highly accurately the exact results well beyond the regime of the rotating-wave approximation.
基金Supported by National Natural Science Foundation of China(51307120,51477117).
文摘The magnetically coupled resonant wireless power transfer(MCR-WPT)system for implantable medical devices has gradually become one of the research hotspots.The transmission characteristics of the system in weak-coupling regions are of research significance.The mathematical model of the system's transmission characteristics is established by equivalent circuit theory.Several key factors that affect the transmission characteristics of the system are obtained,to include the self-inductance of the coil,the mutual inductance between the coils,and the load resistance.A magnetically coupled resonant wireless power transfer system is designed.A method of coil design is proposed.The transmission efficiency of the system in the weak-coupling region is improved by optimizing the design of the coil.Simulation and experimental results exhibited good consistency.The results show that the transmission performance of the system in the weak-coupling area is improved.This work provides guidance and practical significance for the research of the MCR-WPT system with implantable medical equipment.
