We investigate the coupling of two superconducting quantum interference devices (SQUIDs) via a metallicnanomechanical resonator (NAMR),and bring out the effective interaction between the two SQUIDs.By constructingthe ...We investigate the coupling of two superconducting quantum interference devices (SQUIDs) via a metallicnanomechanical resonator (NAMR),and bring out the effective interaction between the two SQUIDs.By constructingthe evolution operator,we also study the evolvement of entanglement in this composed system.展开更多
A good cooling circle should ensure that the system can work at an appropriate temperature in the requirements of power increase,engine compartment constraint and working demands for modern engineering machinery,which...A good cooling circle should ensure that the system can work at an appropriate temperature in the requirements of power increase,engine compartment constraint and working demands for modern engineering machinery,which asks for a thorough understanding of system thermal loads before practical production.However,traditional experiment method spends a long time,costs a huge resource but lacks efficiency,whereas virtual design can avoid the shortcomings of traditional method and can analyze operating states adequately with variable loads on engine,generator,drives,battery pack and HVAC systems.Therefore,this paper focuses on a new virtual design method based on multi-dimension coupled simulation adopting Flowmaster software for initial prediction and CFX tool for further optimization.The simulation results in different operating conditions are compared and validated with experiments.Orthogonal experiment and range analysis are used to explore key parameters of cooling system.The research will be helpful in guiding future design and optimization of engineering machinery.展开更多
In this review, we briefly review recent works on hybrid (nano) and diamond nitrogen-vacancy (NV) centers. We also review opto-mechanical systems that contain both mechanical oscillators two different types of mec...In this review, we briefly review recent works on hybrid (nano) and diamond nitrogen-vacancy (NV) centers. We also review opto-mechanical systems that contain both mechanical oscillators two different types of mechanical oscillators. The first one is a clamped mechanical oscillator, such as a cantilever, with a fixed frequency. The second one is an optically trapped nano-diamond with a built-in nitrogen-vacancy center. By coupling mechanical resonators with electron spins, we can use the spins to control the motion of mechanical oscillators. For the first setup, we discuss two different coupling mechanisms, which are magnetic coupling and strain induced coupling. We summarize their applications such as cooling the mechanical oscillator, generating entanglements between NV centers, squeezing spin ensembles etc. For the second setup, we discuss how to generate quantum superposition states with magnetic coupling, and realize matter wave interferometer. We will also review its applications as ultra-sensitive mass spectrometer. Finally, we discuss new coupling mechanisms and applications of the field.展开更多
Stationary entanglement in a four-mode optomechanical system,especially under room-temperature,is discussed.In this scheme,when the coupling strengths between the two target modes and the mechanical resonator are equa...Stationary entanglement in a four-mode optomechanical system,especially under room-temperature,is discussed.In this scheme,when the coupling strengths between the two target modes and the mechanical resonator are equal,the results cannot be explained by the Bogoliubov-mode-based scheme.This is related to the idea of quantummechanics-free subspace,which plays an important role when the thermal noise of the mechanical modes is considered.Significantly prominent steady-state entanglement can be available under room-temperature.展开更多
基金Supported by the Fundamental Research Punds for the Central Universities under Grant No. DUT10LK10the National Science Foundation of China under Grant Nos. 60703100 and 10875020
文摘We investigate the coupling of two superconducting quantum interference devices (SQUIDs) via a metallicnanomechanical resonator (NAMR),and bring out the effective interaction between the two SQUIDs.By constructingthe evolution operator,we also study the evolvement of entanglement in this composed system.
基金supported by the Natural Science Foundation of Fujian Province of China(Grant No.2014J01210)Knowledge Innovation of Shenzhen City of China(Grant No.JCYJ20140417162429675)National Key Technology R&D Program of China(Grant No.2013BAF07B04)
文摘A good cooling circle should ensure that the system can work at an appropriate temperature in the requirements of power increase,engine compartment constraint and working demands for modern engineering machinery,which asks for a thorough understanding of system thermal loads before practical production.However,traditional experiment method spends a long time,costs a huge resource but lacks efficiency,whereas virtual design can avoid the shortcomings of traditional method and can analyze operating states adequately with variable loads on engine,generator,drives,battery pack and HVAC systems.Therefore,this paper focuses on a new virtual design method based on multi-dimension coupled simulation adopting Flowmaster software for initial prediction and CFX tool for further optimization.The simulation results in different operating conditions are compared and validated with experiments.Orthogonal experiment and range analysis are used to explore key parameters of cooling system.The research will be helpful in guiding future design and optimization of engineering machinery.
基金supported by the National Basic Research Program of China(Grant Nos.2011CBA00300 and 2011CBA00302)the National Natural Science Foundation of China(Grant Nos.11105136,61435007,11374032 and11121403)+1 种基金the National Key Basic Research Program of China(Grant No.2014CB848700)the support given by Purdue University through the startup fund
文摘In this review, we briefly review recent works on hybrid (nano) and diamond nitrogen-vacancy (NV) centers. We also review opto-mechanical systems that contain both mechanical oscillators two different types of mechanical oscillators. The first one is a clamped mechanical oscillator, such as a cantilever, with a fixed frequency. The second one is an optically trapped nano-diamond with a built-in nitrogen-vacancy center. By coupling mechanical resonators with electron spins, we can use the spins to control the motion of mechanical oscillators. For the first setup, we discuss two different coupling mechanisms, which are magnetic coupling and strain induced coupling. We summarize their applications such as cooling the mechanical oscillator, generating entanglements between NV centers, squeezing spin ensembles etc. For the second setup, we discuss how to generate quantum superposition states with magnetic coupling, and realize matter wave interferometer. We will also review its applications as ultra-sensitive mass spectrometer. Finally, we discuss new coupling mechanisms and applications of the field.
基金Supported by National Natural Science Foundation of China under Grant No.11174109
文摘Stationary entanglement in a four-mode optomechanical system,especially under room-temperature,is discussed.In this scheme,when the coupling strengths between the two target modes and the mechanical resonator are equal,the results cannot be explained by the Bogoliubov-mode-based scheme.This is related to the idea of quantummechanics-free subspace,which plays an important role when the thermal noise of the mechanical modes is considered.Significantly prominent steady-state entanglement can be available under room-temperature.