Schemes for two-qubit and three-qubit controlled gates based on cross-Kerr nonlinearity are proposed in this paper.The probability of the success of these gates can be increased by quantum nondemolition detectors,whic...Schemes for two-qubit and three-qubit controlled gates based on cross-Kerr nonlinearity are proposed in this paper.The probability of the success of these gates can be increased by quantum nondemolition detectors,which are used to judge which paths the signal photons pass through.These schemes are almost deterministic and require no ancilla photon.The advantages of these gates over the existing ones include less resource consumption and a higher probability of success,which make our schemes more feasible with current technology.展开更多
We present a scheme for implementing locally a nonlocal N-target controlled–controlled gate with unit probability of success by harnessing two（N＋1）-qubit Greenberger–Horne–Zeilinger（GHZ） states as quantum chan...We present a scheme for implementing locally a nonlocal N-target controlled–controlled gate with unit probability of success by harnessing two（N＋1）-qubit Greenberger–Horne–Zeilinger（GHZ） states as quantum channel and N qutrits as catalyser. The quantum network that implements this nonlocal（N＋2）-body gate is built entirely of local single-body and two-body gates, and has only（3N＋2） two-body gates. This result suggests that both the computational depth of quantum network and the quantum resources required to perform this nonlocal gate might be significantly reduced. This scheme can be generalized straightforwardly to implement a nonlocal N-target and M-control qubits gate.展开更多
This paper presents a very simple scheme for generating quantum controlled phase-shift gate with only one step by using the two vibrational modes of a trapped ion as the two qubits. The scheme couples two vibration de...This paper presents a very simple scheme for generating quantum controlled phase-shift gate with only one step by using the two vibrational modes of a trapped ion as the two qubits. The scheme couples two vibration degrees of freedom coupled with a suitable chosen laser excitation via the ionic states.展开更多
In this paper, we give an efficient physical realization of a double-slit duality quantum gate. Weak cross- Kerr nonlinearity is exploited here. The probability of success can reach 1/2. Asymmetrical slit duality cont...In this paper, we give an efficient physical realization of a double-slit duality quantum gate. Weak cross- Kerr nonlinearity is exploited here. The probability of success can reach 1/2. Asymmetrical slit duality control gate also can be constructed conveniently. The special quantum control gate could be realized easily in optical system by our current experimental technology.展开更多
This paper presents a direct implementation scheme of the non-local multi-qubit controlled phase gate by using optical fibres and adiabatic passage. The smaller operation number for implementing the multi-qubit contro...This paper presents a direct implementation scheme of the non-local multi-qubit controlled phase gate by using optical fibres and adiabatic passage. The smaller operation number for implementing the multi-qubit controlled phase gate and needlessness for addressing individually save physical resource and lower the difficulties of experiment. Mean- while, the scheme is immune from some decoherence effects such as the atomic spontaneous emission and fibre loss. In principle, it is scalable.展开更多
The simple gate control system which is made of traditional manual or proximity switch cannot meet the requirements of connecting with the computer monitoring system of hydropower station, it must be reformed. On the ...The simple gate control system which is made of traditional manual or proximity switch cannot meet the requirements of connecting with the computer monitoring system of hydropower station, it must be reformed. On the basis of the integrated analysis for small hydropower station, the paper discussed the singlechip as the core to realize the methods of gate automatic control system in small hydropower station. The designs for hardware and software of gate control system were introduced. And the control system was reformed from customary manual control to computer automatic control. The simulation experiment shows that this scheme is feasible.展开更多
At present,super-resolution algorithms are employed to tackle the challenge of low image resolution,but it is difficult to extract differentiated feature details based on various inputs,resulting in poor generalizatio...At present,super-resolution algorithms are employed to tackle the challenge of low image resolution,but it is difficult to extract differentiated feature details based on various inputs,resulting in poor generalization ability.Given this situation,this study first analyzes the features of some feature extraction modules of the current super-resolution algorithm and then proposes an adaptive feature fusion block(AFB)for feature extraction.This module mainly comprises dynamic convolution,attention mechanism,and pixel-based gating mechanism.Combined with dynamic convolution with scale information,the network can extract more differentiated feature information.The introduction of a channel spatial attention mechanism combined with multi-feature fusion further enables the network to retain more important feature information.Dynamic convolution and pixel-based gating mechanisms enhance the module’s adaptability.Finally,a comparative experiment of a super-resolution algorithm based on the AFB module is designed to substantiate the efficiency of the AFB module.The results revealed that the network combined with the AFB module has stronger generalization ability and expression ability.展开更多
Electron spin qubits[1]in Si have attracted wide attention as potentially viable building blocks for a scalable quantum computer,as illustrated by recent experiments showing highfidelity single-qubit and two-qubit gat...Electron spin qubits[1]in Si have attracted wide attention as potentially viable building blocks for a scalable quantum computer,as illustrated by recent experiments showing highfidelity single-qubit and two-qubit gates[1-4].With magnetic interactions relatively weak and difficult to control,the prevailing means for spin manipulation has been through electrically controlled top gates on the semiconductor heterostructures,helped by a nearby micromagnet and the magnetic field gradient it induces,which leads to an artificial spin-orbit coupling[5].展开更多
The simultaneous modulation of electric and optical properties in graphene is essential for advancing high-performance applications in optoelectronics.However,achieving in-situ control of multiple electric and optical...The simultaneous modulation of electric and optical properties in graphene is essential for advancing high-performance applications in optoelectronics.However,achieving in-situ control of multiple electric and optical states in graphene devices remains a challenge.Here we demonstrate a versatile and reversible electric-field control of organic-ion intercalation from bilayer to pentalayer graphene.Through simultaneous optical imaging and electric measurements,we reveal multiple physical states controlled by the layer-by-layer intercalation processes,resulting in both high transparency and high electric conductance with an increase in the number of intercalated layers.Raman spectroscopy demonstrates that the intercalated graphene maintains a high carrier concentration without lattice degradation.Moreover,Hall effect measurements reveal that the carrier density can reach approximately 1.5×10^(14)cm^(-2)per layer.The ability to synchronously control the transparency and conductance states by adjusting the number of ion-intercalated layers highlights the potential of multistate modulation for the development of advanced optoelectronic devices in two-dimensional materials.展开更多
The cold atom qubit platform emerges as an attractive choice for the next stage of quantum computation research,where a special family of synthetic analytical pulses has considerably improved the experimental performa...The cold atom qubit platform emerges as an attractive choice for the next stage of quantum computation research,where a special family of synthetic analytical pulses has considerably improved the experimental performance of Controlled-PHASE Rydberg blockade gates in recent studies.The success of Controlled-PHASE Rydberg blockade gates triggers the intriguing question of whether the two-qubit Rydberg blockade gate SWAP gate exists.Via investigating the transition linkage structure,we provide a definitive answer to this question and establish the method of fast SWAP Rydberg blockade gates with synthetic continuously modulated driving.These gate protocols use careful analysis to properly generate coherent population transfer and phase accumulation of the wave function in the atom-laser interaction process.They can adapt to finite Rydberg blockade strengths and bear considerable resistance to some major adverse effects such as laser fluctuations.Further examinations reveal that we can anticipate satisfying performances of the method with currently available experimental techniques in relevant research areas.展开更多
In this paper, two schemes for teleporting an unknown two-particle entangled state from the sender （Alice） to the receiver （Bob） via a four-particle entangled cluster state are proposed. In these two schemes, the ...In this paper, two schemes for teleporting an unknown two-particle entangled state from the sender （Alice） to the receiver （Bob） via a four-particle entangled cluster state are proposed. In these two schemes, the unknown twoparticle entangled state can be teleported perfectly. The successful probabilities and fidelities of the schemes can reach unity.展开更多
In 1905, Henry Head first suggested that trans- mission of pain-related protopathic information can be negatively modulated by inputs from afferents sensing innocuous touch and temperature. In 1965, Melzak and Wall pr...In 1905, Henry Head first suggested that trans- mission of pain-related protopathic information can be negatively modulated by inputs from afferents sensing innocuous touch and temperature. In 1965, Melzak and Wall proposed a more concrete gate control theory of pain that highlights the interaction between unmyelinated C fibers and myelinated A fibers in pain transmission. Here we review the current understanding of the spinal micro- circuits transmitting and gating mechanical pain or itch. We also discuss how disruption of the gate control could cause pain or itch evoked by innocuous mechanical stimuli, a hallmark symptom for many chronic pain or itch patients.展开更多
This paper proposes an experimentally feasible scheme for teleportation of an unknown two-atom entangled state, where a cluster state is used as the quantum channel. This scheme does not need any joint measurement. In...This paper proposes an experimentally feasible scheme for teleportation of an unknown two-atom entangled state, where a cluster state is used as the quantum channel. This scheme does not need any joint measurement. In addition, the successful probability and fidelity of teleportation can both reach 1.0. The current scheme can be realized within the current experimental technology.展开更多
A low molecular weight gelator with dual pH and glucose sensitive moieties was synthesized. The gelator penetrated in the mesopores of silica nanoparticles(MSNs) and formed low molecular weight gel(LMWG) as gate to fa...A low molecular weight gelator with dual pH and glucose sensitive moieties was synthesized. The gelator penetrated in the mesopores of silica nanoparticles(MSNs) and formed low molecular weight gel(LMWG) as gate to fabricate dual pH and glucose responsive nano drug delivery system. Antidiabetic drug was loaded in the gel caped MSNs, the drug release was responsive to the pH and glucose levels and the drug release could be controlled via the stimuli sensitivity of gel.展开更多
We present two schemes for preparing cluster states with atomic qubits in an ion-trap system. In the first scheme an auxiliary atomic level is needed. While in the second scheme an additional classical driven field is...We present two schemes for preparing cluster states with atomic qubits in an ion-trap system. In the first scheme an auxiliary atomic level is needed. While in the second scheme an additional classical driven field is used, and the multi-ion cluster states can be generated by one step. Both the schemes are insensitive to thermal motion of the ions, all the facilities used in them are well within state of the art.展开更多
An experimentally feasible scheme for teleportation of an unknown two-atom entangled state is proposed. Our scheme uses a duster state as the quantum channel, where we do not need any joint Bell-state measurement. Mor...An experimentally feasible scheme for teleportation of an unknown two-atom entangled state is proposed. Our scheme uses a duster state as the quantum channel, where we do not need any joint Bell-state measurement. Moreover the successful probability and fidelity of teleportation can both reach 1.0. The current scheme can be realized within the current experimental technology.展开更多
We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state...We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state of the cavity. In particular, we have managed to avoid the conventional dispersive coupling so that high speed gate operation is achieved which is very important in view of decoherence. We show that this multipartite pair-wise controlled phase operation makes the generation of two-dimensional cluster states very efficient.展开更多
In this paper, we study quantum teleportation of atomic states via a hybrid entangled state （HES） involving an atom and a cavity field. And we investigate how to implement controlled phase （CP） gates between atomi...In this paper, we study quantum teleportation of atomic states via a hybrid entangled state （HES） involving an atom and a cavity field. And we investigate how to implement controlled phase （CP） gates between atomic internal states and coherent states of cavity field. We also discuss the methods of distinguishing coherent states [±α〉 in a cavity. Finally, a brief discussion about the feasibility of this scheme in experiment is presented.展开更多
We explore the possibility of an N-qubit （N 〉 3） Grover search in cavity QED, based on a fast operation of an N-qubit controlled phase-flip with atoms in resonance with the cavity mode. We demonstrate both analytic...We explore the possibility of an N-qubit （N 〉 3） Grover search in cavity QED, based on a fast operation of an N-qubit controlled phase-flip with atoms in resonance with the cavity mode. We demonstrate both analytically and numerically that our scheme can be achieved efficiently to find a marked state with high fidelity and high success probability. As an example, a ten-qubit Grover search is simulated specifically under the discussion of experimental feasibility and challenge. We argue that our scheme is applicable to the case involving an arbitrary number of qubits. As cavity decay is involved in our quantum trajectory treatment, we can analytically understand the implementation of a Grover search subject to dissipation, which will be very helpful for relevant experiments.展开更多
We present an efficient scheme for the complete analysis of hyperentangled Greenberger–Horne–Zeilinger(GHZ)state in polarization and time-bin degrees of freedom with two steps. Firstly, the polarization GHZ state is...We present an efficient scheme for the complete analysis of hyperentangled Greenberger–Horne–Zeilinger(GHZ)state in polarization and time-bin degrees of freedom with two steps. Firstly, the polarization GHZ state is distinguished completely and nondestructively, resorting to the controlled phase flip(CPF) gate constructed by the cavity-assisted interaction. Subsequently, the time-bin GHZ state is analyzed by using the preserved polarization entanglement. With the help of CPF gate and self-assisted mechanism, our scheme can be directly generalized to the complete N-photon hyperentangled GHZ state analysis, and it may have potential applications in the hyperentanglement-based quantum communication.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61068001 and 11264042)the Program for Chun Miao Excellent Talents of Department of Education of Jilin Province,China (Grant No. 201316)
文摘Schemes for two-qubit and three-qubit controlled gates based on cross-Kerr nonlinearity are proposed in this paper.The probability of the success of these gates can be increased by quantum nondemolition detectors,which are used to judge which paths the signal photons pass through.These schemes are almost deterministic and require no ancilla photon.The advantages of these gates over the existing ones include less resource consumption and a higher probability of success,which make our schemes more feasible with current technology.
基金Project supported by the Natural Science Foundation of Guangdong Province,China(Grant No.6029431)
文摘We present a scheme for implementing locally a nonlocal N-target controlled–controlled gate with unit probability of success by harnessing two（N＋1）-qubit Greenberger–Horne–Zeilinger（GHZ） states as quantum channel and N qutrits as catalyser. The quantum network that implements this nonlocal（N＋2）-body gate is built entirely of local single-body and two-body gates, and has only（3N＋2） two-body gates. This result suggests that both the computational depth of quantum network and the quantum resources required to perform this nonlocal gate might be significantly reduced. This scheme can be generalized straightforwardly to implement a nonlocal N-target and M-control qubits gate.
基金supported by the National Natural Science Foundation of China (Grant No 10574001)the Program of the Education Department of Anhui Province (2004kj029) of China+1 种基金the Talent Foundation of Anhui University of Chinathe Youth Program of Fuyang Teachers College of China (Grant Nos 2005LQ03 and 2005LQ04)
文摘This paper presents a very simple scheme for generating quantum controlled phase-shift gate with only one step by using the two vibrational modes of a trapped ion as the two qubits. The scheme couples two vibration degrees of freedom coupled with a suitable chosen laser excitation via the ionic states.
基金Supported by National Natural Science Foundation of China under Grant Nos.10775076 and 10874098the National Basic Research Program of China under Grant No.2009CB929402the Specialized Research Fund for the Doctoral Program of Education Ministry of China under Grant No.20060003048
文摘In this paper, we give an efficient physical realization of a double-slit duality quantum gate. Weak cross- Kerr nonlinearity is exploited here. The probability of success can reach 1/2. Asymmetrical slit duality control gate also can be constructed conveniently. The special quantum control gate could be realized easily in optical system by our current experimental technology.
基金Project supported by the National Natural Science Foundation of China (Grant No 10574022)Natural Science Foundation of Fujian Province of China (Grant Nos 2007J0002 and 2006J0230)Foundation for Universities in Fujian Province (Grant No 2007F5041)
文摘This paper presents a direct implementation scheme of the non-local multi-qubit controlled phase gate by using optical fibres and adiabatic passage. The smaller operation number for implementing the multi-qubit controlled phase gate and needlessness for addressing individually save physical resource and lower the difficulties of experiment. Mean- while, the scheme is immune from some decoherence effects such as the atomic spontaneous emission and fibre loss. In principle, it is scalable.
文摘The simple gate control system which is made of traditional manual or proximity switch cannot meet the requirements of connecting with the computer monitoring system of hydropower station, it must be reformed. On the basis of the integrated analysis for small hydropower station, the paper discussed the singlechip as the core to realize the methods of gate automatic control system in small hydropower station. The designs for hardware and software of gate control system were introduced. And the control system was reformed from customary manual control to computer automatic control. The simulation experiment shows that this scheme is feasible.
基金Supported by Sichuan Science and Technology Program(2021YFQ0003,2023YFSY0026,2023YFH0004).
文摘At present,super-resolution algorithms are employed to tackle the challenge of low image resolution,but it is difficult to extract differentiated feature details based on various inputs,resulting in poor generalization ability.Given this situation,this study first analyzes the features of some feature extraction modules of the current super-resolution algorithm and then proposes an adaptive feature fusion block(AFB)for feature extraction.This module mainly comprises dynamic convolution,attention mechanism,and pixel-based gating mechanism.Combined with dynamic convolution with scale information,the network can extract more differentiated feature information.The introduction of a channel spatial attention mechanism combined with multi-feature fusion further enables the network to retain more important feature information.Dynamic convolution and pixel-based gating mechanisms enhance the module’s adaptability.Finally,a comparative experiment of a super-resolution algorithm based on the AFB module is designed to substantiate the efficiency of the AFB module.The results revealed that the network combined with the AFB module has stronger generalization ability and expression ability.
文摘Electron spin qubits[1]in Si have attracted wide attention as potentially viable building blocks for a scalable quantum computer,as illustrated by recent experiments showing highfidelity single-qubit and two-qubit gates[1-4].With magnetic interactions relatively weak and difficult to control,the prevailing means for spin manipulation has been through electrically controlled top gates on the semiconductor heterostructures,helped by a nearby micromagnet and the magnetic field gradient it induces,which leads to an artificial spin-orbit coupling[5].
基金supported by the National Natural Science Foundation of China(Grant Nos.12274252,and 12350404)the Basic Science Center Project of NSFC(Grant No.52388201)the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302502)。
文摘The simultaneous modulation of electric and optical properties in graphene is essential for advancing high-performance applications in optoelectronics.However,achieving in-situ control of multiple electric and optical states in graphene devices remains a challenge.Here we demonstrate a versatile and reversible electric-field control of organic-ion intercalation from bilayer to pentalayer graphene.Through simultaneous optical imaging and electric measurements,we reveal multiple physical states controlled by the layer-by-layer intercalation processes,resulting in both high transparency and high electric conductance with an increase in the number of intercalated layers.Raman spectroscopy demonstrates that the intercalated graphene maintains a high carrier concentration without lattice degradation.Moreover,Hall effect measurements reveal that the carrier density can reach approximately 1.5×10^(14)cm^(-2)per layer.The ability to synchronously control the transparency and conductance states by adjusting the number of ion-intercalated layers highlights the potential of multistate modulation for the development of advanced optoelectronic devices in two-dimensional materials.
基金Science and Technology Commission of Shanghai Municipality(24DP2600202)National Key Research and Development Program of China(2024YFB4504002)National Natural Science Foundation of China(92165107)。
文摘The cold atom qubit platform emerges as an attractive choice for the next stage of quantum computation research,where a special family of synthetic analytical pulses has considerably improved the experimental performance of Controlled-PHASE Rydberg blockade gates in recent studies.The success of Controlled-PHASE Rydberg blockade gates triggers the intriguing question of whether the two-qubit Rydberg blockade gate SWAP gate exists.Via investigating the transition linkage structure,we provide a definitive answer to this question and establish the method of fast SWAP Rydberg blockade gates with synthetic continuously modulated driving.These gate protocols use careful analysis to properly generate coherent population transfer and phase accumulation of the wave function in the atom-laser interaction process.They can adapt to finite Rydberg blockade strengths and bear considerable resistance to some major adverse effects such as laser fluctuations.Further examinations reveal that we can anticipate satisfying performances of the method with currently available experimental techniques in relevant research areas.
基金The project supported by the National Natural Science Foundation of China under Grant No. 60678022, the Key Program of the Education Department of Anhui Province under Grant Nos. 2006KJ070A, 2006KJ057B and the Talent Foundation of Anhui University
文摘In this paper, two schemes for teleporting an unknown two-particle entangled state from the sender （Alice） to the receiver （Bob） via a four-particle entangled cluster state are proposed. In these two schemes, the unknown twoparticle entangled state can be teleported perfectly. The successful probabilities and fidelities of the schemes can reach unity.
基金supported by NIH Grants(R01 NS086372 and R01 DE018025)
文摘In 1905, Henry Head first suggested that trans- mission of pain-related protopathic information can be negatively modulated by inputs from afferents sensing innocuous touch and temperature. In 1965, Melzak and Wall proposed a more concrete gate control theory of pain that highlights the interaction between unmyelinated C fibers and myelinated A fibers in pain transmission. Here we review the current understanding of the spinal micro- circuits transmitting and gating mechanical pain or itch. We also discuss how disruption of the gate control could cause pain or itch evoked by innocuous mechanical stimuli, a hallmark symptom for many chronic pain or itch patients.
基金Project supported by the National Natural Science Foundation of China (Grant No 60678022)the Doctoral Fund of Ministry of Education of China (Grant No 20060357008)+2 种基金the Key Program of the Education Department of Anhui Province, China (Grant No 2006KJ070A)the Program of the Education Department of Anhui Province, China (Grant No 2006KJ057B)the Talent Foundation of Anhui University, China, Anhui Key Laboratory of Information Materials and Devices, China (Anhui University)
文摘This paper proposes an experimentally feasible scheme for teleportation of an unknown two-atom entangled state, where a cluster state is used as the quantum channel. This scheme does not need any joint measurement. In addition, the successful probability and fidelity of teleportation can both reach 1.0. The current scheme can be realized within the current experimental technology.
基金the National Natural Science Foundation of China(No.21672164)the Natural Science Foundation of Zhejiang Province(No.LY15B020001)for the financial support
文摘A low molecular weight gelator with dual pH and glucose sensitive moieties was synthesized. The gelator penetrated in the mesopores of silica nanoparticles(MSNs) and formed low molecular weight gel(LMWG) as gate to fabricate dual pH and glucose responsive nano drug delivery system. Antidiabetic drug was loaded in the gel caped MSNs, the drug release was responsive to the pH and glucose levels and the drug release could be controlled via the stimuli sensitivity of gel.
基金The project supported by the Scientific Research Fund of the Education Department of Hunan Province under Grant No.06C354the Natural Science Foundation of Hunan Province under Grant No.06JJ5015
文摘We present two schemes for preparing cluster states with atomic qubits in an ion-trap system. In the first scheme an auxiliary atomic level is needed. While in the second scheme an additional classical driven field is used, and the multi-ion cluster states can be generated by one step. Both the schemes are insensitive to thermal motion of the ions, all the facilities used in them are well within state of the art.
基金National Natural Science Foundation of China under Grant Nos.60678022 and 1070400the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No.20060357008+3 种基金Natural Science Foundation of Anhui Province under Grant No.070412060the Key Program of the Education Department of Anhui Province under Grant No.2006KJ070AThe Talent Foundation of Anhui UniversityAnhui Key Laboratory of Information Materials and Devices (Anhui University)
文摘An experimentally feasible scheme for teleportation of an unknown two-atom entangled state is proposed. Our scheme uses a duster state as the quantum channel, where we do not need any joint Bell-state measurement. Moreover the successful probability and fidelity of teleportation can both reach 1.0. The current scheme can be realized within the current experimental technology.
基金Project supported by the National Fundamental Research Program of China (Grant No. 2013CB921804)the National Natural Science Foundation of China(Grant No. 11004065)+1 种基金the Natural Science Foundation of Guangdong Province of China (Grant Nos. 10451063101006312 and S2011040000403)the Funds of the Education Department of Anhui Province of China (Grant Nos. KJ2010A323, 2010SQRL187, and KJ2012B075)
文摘We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state of the cavity. In particular, we have managed to avoid the conventional dispersive coupling so that high speed gate operation is achieved which is very important in view of decoherence. We show that this multipartite pair-wise controlled phase operation makes the generation of two-dimensional cluster states very efficient.
基金The project supported by the Scientific Research Fund of Education Department of Hunan Province under Grant No.06C354 and the Natural Science Foundation of Hunan Province under Grant No. 06JJ5015 tCorresponding author,
文摘In this paper, we study quantum teleportation of atomic states via a hybrid entangled state （HES） involving an atom and a cavity field. And we investigate how to implement controlled phase （CP） gates between atomic internal states and coherent states of cavity field. We also discuss the methods of distinguishing coherent states [±α〉 in a cavity. Finally, a brief discussion about the feasibility of this scheme in experiment is presented.
基金Project supported by National Natural Science Foundation of China (Grant Nos 10474118, 60490280 and 10774161)partly by the National Fundamental Research Program of China (Grants Nos 2005CB724502 and 2006CB921203)
文摘We explore the possibility of an N-qubit （N 〉 3） Grover search in cavity QED, based on a fast operation of an N-qubit controlled phase-flip with atoms in resonance with the cavity mode. We demonstrate both analytically and numerically that our scheme can be achieved efficiently to find a marked state with high fidelity and high success probability. As an example, a ten-qubit Grover search is simulated specifically under the discussion of experimental feasibility and challenge. We argue that our scheme is applicable to the case involving an arbitrary number of qubits. As cavity decay is involved in our quantum trajectory treatment, we can analytically understand the implementation of a Grover search subject to dissipation, which will be very helpful for relevant experiments.
文摘We present an efficient scheme for the complete analysis of hyperentangled Greenberger–Horne–Zeilinger(GHZ)state in polarization and time-bin degrees of freedom with two steps. Firstly, the polarization GHZ state is distinguished completely and nondestructively, resorting to the controlled phase flip(CPF) gate constructed by the cavity-assisted interaction. Subsequently, the time-bin GHZ state is analyzed by using the preserved polarization entanglement. With the help of CPF gate and self-assisted mechanism, our scheme can be directly generalized to the complete N-photon hyperentangled GHZ state analysis, and it may have potential applications in the hyperentanglement-based quantum communication.
