We propose an experimental scheme for implementing the optimal 1 → 3 real state cloning via linear optical elements. This method relies on one polarized qubit and two location qubits and is feasible with current expe...We propose an experimental scheme for implementing the optimal 1 → 3 real state cloning via linear optical elements. This method relies on one polarized qubit and two location qubits and is feasible with current experimental technology.展开更多
We present an optical scheme to almost completely teleport a bipartite entangled coherent state using afour-partite cluster-type entangled coherent state as quantum channel.The scheme is based on optical elements such...We present an optical scheme to almost completely teleport a bipartite entangled coherent state using afour-partite cluster-type entangled coherent state as quantum channel.The scheme is based on optical elements suchas beam splitters,phase shifters,and photon detectors.We also obtain the average fidelity of the teleportation process.It is shown that the average fidelity is quite close to unity if the mean photon number of the coherent state is not toosmall.展开更多
We study cavity optomechanics of ultracold dual-species atomic mixtures with nonlinear collisions.Interspecies interactions provide a direct parametric coupling of fictitious mechanical elements which,through interfer...We study cavity optomechanics of ultracold dual-species atomic mixtures with nonlinear collisions.Interspecies interactions provide a direct parametric coupling of fictitious mechanical elements which,through interfering with the intracavity optical field,leads to a switchable optically-dark state for either species.This demonstrates a matterwave analog of recently observed mechanical wave mixing and quantum motional-state swapping,with applications in the construction of integrated phononic devices,and the cavity-enhanced detection of quantum degenerate atomic mixtures.展开更多
We present a universal way to concentrate an arbitrary N-particle less-entangled W state into a maximally entangled W state with different parity check gates.It comprises two protocols.The first protocol is based on t...We present a universal way to concentrate an arbitrary N-particle less-entangled W state into a maximally entangled W state with different parity check gates.It comprises two protocols.The first protocol is based on the linear optical elements,say the partial parity check gate and the second protocol uses the quantum nondemolition measurement to construct the complete parity check gate.Both protocols can achieve the concentration task.These protocols have several advantages.First,they can obtain a maximally entangled W state only with the help of some single photons,which greatly reduces the number of entanglement resources.Second,in the first protocol,only linear optical elements are required,which is feasible with current techniques.Third,the second protocol can be repeated to perform the concentration step and obtain a higher success probability.All these advantages make it quite useful in current quantum communication and computation applications.展开更多
Flexible energy storage devices are becoming indispensable new elements of wearable electronics to improve our living qualities.As the main energy storage devices,lithium-ion batteries(LIBs)are gradually approaching t...Flexible energy storage devices are becoming indispensable new elements of wearable electronics to improve our living qualities.As the main energy storage devices,lithium-ion batteries(LIBs)are gradually approaching their theoretical limit in terms of energy density.In recent years,lithium metal batteries(LMBs)with metallic Li as the anode are revived due to the extremely high energy density,and are considered to be one of the ideal alternatives for the next generation of flexible power supply.In this review,key technologies and scientific problems to be overcome for flexible LMBs are discussed.Then,the recent advances in flexible LMBs,including the design of flexible Li metal anodes,electrolytes,cathodes and interlayers,are summarized.In addition,we have summed up the research progress of flexible device configurations,and emphasized the importance of flexibility evaluation and functionality integration to ensure the wearing safety in complex environment.Finally,the challenges and future development of flexible LMBs are summarized and prospected.展开更多
Transistor size is constantly being reduced to improve performance as well as power consumption. For the channel length to be reduced, the corresponding gate dielectric thickness should also be reduced. Unfortunately,...Transistor size is constantly being reduced to improve performance as well as power consumption. For the channel length to be reduced, the corresponding gate dielectric thickness should also be reduced. Unfortunately, graphene devices are more complicated due to an extra capacitance called quantum capacitance (CQ) which limits the effective gate dielectric reduction. In this work, we analyzed the effect of CQ on device-scaling issues by extracting it from scaling of the channel length of devices. In contrast to previous reports for metal-insulator- metal structures, a practical device structure was used in conjunction with direct radio-frequency field-effect transistor measurements to describe the graphene channels. In order to precisely extract device parameters, we reassessed the equivalent circuit, and concluded that the on-state model should in fact be used. By careful consideration of the underlap region, our device modeling was shown to be in good agreement with the experimental data. CQ contributions to equivalent oxide thickness were analyzed in detail for varying impurity concentrations in graphene. Finally, we were able to demonstrate that despite contributions from CQ, graphene's high mobility and low-voltage operation allows for ~raphene channels suitable for next generation transistors.展开更多
文摘We propose an experimental scheme for implementing the optimal 1 → 3 real state cloning via linear optical elements. This method relies on one polarized qubit and two location qubits and is feasible with current experimental technology.
基金Supported by the National Natural Science Foundation of China under Grant No.60708003the National Key Basic Research Program of China under Grant No.2006CB921604the Basic Key Program of Shanghai Municipality under Grant No.07JC14017
文摘We present an optical scheme to almost completely teleport a bipartite entangled coherent state using afour-partite cluster-type entangled coherent state as quantum channel.The scheme is based on optical elements suchas beam splitters,phase shifters,and photon detectors.We also obtain the average fidelity of the teleportation process.It is shown that the average fidelity is quite close to unity if the mean photon number of the coherent state is not toosmall.
基金Supports of the National Natural Science Foundation of China under Grant No. 10974045the Fok Y-T Education Foundation,and the Henan Chuangxin Program
文摘We study cavity optomechanics of ultracold dual-species atomic mixtures with nonlinear collisions.Interspecies interactions provide a direct parametric coupling of fictitious mechanical elements which,through interfering with the intracavity optical field,leads to a switchable optically-dark state for either species.This demonstrates a matterwave analog of recently observed mechanical wave mixing and quantum motional-state swapping,with applications in the construction of integrated phononic devices,and the cavity-enhanced detection of quantum degenerate atomic mixtures.
基金supported by the National Natural Science Foundation of China(Grant Nos.11474168and 61401222)the Qing Lan Project in Jiangsu Province+2 种基金Specialized Research Fund for the Doctoral Program of Higher Education(Grant No20113223120002)University Natural Science Research Project of Jiangsu Province(Grant No.11KJB510016)the Priority Academic Development Program of Jiangsu Higher Education Institutions,China
文摘We present a universal way to concentrate an arbitrary N-particle less-entangled W state into a maximally entangled W state with different parity check gates.It comprises two protocols.The first protocol is based on the linear optical elements,say the partial parity check gate and the second protocol uses the quantum nondemolition measurement to construct the complete parity check gate.Both protocols can achieve the concentration task.These protocols have several advantages.First,they can obtain a maximally entangled W state only with the help of some single photons,which greatly reduces the number of entanglement resources.Second,in the first protocol,only linear optical elements are required,which is feasible with current techniques.Third,the second protocol can be repeated to perform the concentration step and obtain a higher success probability.All these advantages make it quite useful in current quantum communication and computation applications.
基金financially supported by the National Natural Science Foundation of China(U1804138,U1904195,and 22104079)the Program for Science&Technology Innovative Research Team(20IRTSTHN007)+2 种基金the Innovation Talents(22HASTIT028)Key Scientific Research(22A150052)in the Universities of Henan Provincethe Key Science and Technology Research of Henan Province(212102210654)。
文摘Flexible energy storage devices are becoming indispensable new elements of wearable electronics to improve our living qualities.As the main energy storage devices,lithium-ion batteries(LIBs)are gradually approaching their theoretical limit in terms of energy density.In recent years,lithium metal batteries(LMBs)with metallic Li as the anode are revived due to the extremely high energy density,and are considered to be one of the ideal alternatives for the next generation of flexible power supply.In this review,key technologies and scientific problems to be overcome for flexible LMBs are discussed.Then,the recent advances in flexible LMBs,including the design of flexible Li metal anodes,electrolytes,cathodes and interlayers,are summarized.In addition,we have summed up the research progress of flexible device configurations,and emphasized the importance of flexibility evaluation and functionality integration to ensure the wearing safety in complex environment.Finally,the challenges and future development of flexible LMBs are summarized and prospected.
文摘Transistor size is constantly being reduced to improve performance as well as power consumption. For the channel length to be reduced, the corresponding gate dielectric thickness should also be reduced. Unfortunately, graphene devices are more complicated due to an extra capacitance called quantum capacitance (CQ) which limits the effective gate dielectric reduction. In this work, we analyzed the effect of CQ on device-scaling issues by extracting it from scaling of the channel length of devices. In contrast to previous reports for metal-insulator- metal structures, a practical device structure was used in conjunction with direct radio-frequency field-effect transistor measurements to describe the graphene channels. In order to precisely extract device parameters, we reassessed the equivalent circuit, and concluded that the on-state model should in fact be used. By careful consideration of the underlap region, our device modeling was shown to be in good agreement with the experimental data. CQ contributions to equivalent oxide thickness were analyzed in detail for varying impurity concentrations in graphene. Finally, we were able to demonstrate that despite contributions from CQ, graphene's high mobility and low-voltage operation allows for ~raphene channels suitable for next generation transistors.