We discuss a quantum remote state preparation protocol by which two parties, Alice and Candy, prepare a single-qubit and a two-qubit state, respectively, at the site of the receiver Bob. The single-qubit state is know...We discuss a quantum remote state preparation protocol by which two parties, Alice and Candy, prepare a single-qubit and a two-qubit state, respectively, at the site of the receiver Bob. The single-qubit state is known to Alice while the two-qubit state which is a non-maximally entangled Bell state is known to Candy. The three parties are connected through a single entangled state which acts as a quantum channel. We first describe the protocol in the ideal case when the entangled channel under use is in a pure state. After that, we consider the effect of amplitude damping(AD) noise on the quantum channel and describe the protocol executed through the noisy channel. The decrement of the fidelity is shown to occur with the increment in the noise parameter. This is shown by numerical computation in specific examples of the states to be created. Finally, we show that it is possible to maintain the label of fidelity to some extent and hence to decrease the effect of noise by the application of weak and reversal measurements. We also present a scheme for the generation of the five-qubit entangled resource which we require as a quantum channel. The generation scheme is run on the IBMQ platform.展开更多
Using two tripartite Greenberger-Horne-Zeilinger （GHZ） states as the shared channels, we investigate the noise effects on the deterministic joint remote preparation of an arbitrary two-qubit state. By unitary matrix...Using two tripartite Greenberger-Horne-Zeilinger （GHZ） states as the shared channels, we investigate the noise effects on the deterministic joint remote preparation of an arbitrary two-qubit state. By unitary matrix decomposition procedure, we first construct the quantum logic circuit of the deterministic joint remote state preparation protocol. Then, we analytically derive the fidelity and the average fidelity for the deterministic joint remote preparation of an arbitrary two- qubit state and of four types of special two-qubit states under the influence of the Pauli noises. It is found that the fidelity depends on the noise types, the qubit-environment coupling strength, and the state to be remotely prepared. Moreover, even if the two GHZ channels are subject to the same environmental noises, the average fidelities for remotely preparing different two-qubit states display different time evolution behaviors. The remote preparation of the identical two-qubit states also shows that the average fidelities affected by different noisy environments exhibit different evolution actions.展开更多
Using a quantum channel consisting of a GHZ state exposed to noisy environment,we investigate how toremotely prepare an entangled state and a qubit state,respectively.By solving the master equation in the Lindbladform...Using a quantum channel consisting of a GHZ state exposed to noisy environment,we investigate how toremotely prepare an entangled state and a qubit state,respectively.By solving the master equation in the Lindbladform,the influence of the various types of noises on the GHZ state is first discussed.Then we use the fidelity to describehow close the remotely prepared state and the initial state are.Our results show that the fidelity is a function of thedecoherence rates and the angles of the initial state.It is found that for each of the two RSP schemes,the influence ofthe noise acting simultaneously in x,y,and z directions on the average fidelity is the strongest while the influence of thenoise acting in x or z direction on the average fidelity is relatively weaker.展开更多
The radiation decay of a two-level atom could be inhibited within structured environments even under longtime evolution.We investigate the stabilized quantum coherence of composite systems undergoing local dissipation...The radiation decay of a two-level atom could be inhibited within structured environments even under longtime evolution.We investigate the stabilized quantum coherence of composite systems undergoing local dissipation and exploit it further as a resource for remote state preparation.We focus on outputs of quantum states with solely quantum discord(i.e.,without entanglement)and demonstrate that they could be resulted from various initial states providing specific spectral structure of the reservoir.In detail,we elaborate the behavior of stabilized quantum discord and the corresponding fidelity for remote state preparation in connection with structural spectra of Ohmic class reservoir and of photonic band gap mediums.展开更多
WITS-Math is a mathematical equation formatting tool in WITS, a multilingual document preparation environment. WITS-Math includes a library manager and an equation formatter. The main task of WITS-Math is to format di...WITS-Math is a mathematical equation formatting tool in WITS, a multilingual document preparation environment. WITS-Math includes a library manager and an equation formatter. The main task of WITS-Math is to format diversities of mathematical equations and organize them into an equation library used by other tools in the WITS environment.WITS-Math is a direct manipulation mathematics editor. It uses syntax directed markup language as the internal representation, alld provides an interactive WYSIWYG interface for users to format equations. WITS-Math provides an equation access mechanism. Other tools can access equations in a library by cross-reference from a source file or through data exchange without knowillg the structure of equation libraries. The common data structure and the rendering object in the WITS platform ensure that the formatted equations can be directly used by other tools.展开更多
基金Project supported by Indian Institute of Engineering Science and Technology, Shibpur, India
文摘We discuss a quantum remote state preparation protocol by which two parties, Alice and Candy, prepare a single-qubit and a two-qubit state, respectively, at the site of the receiver Bob. The single-qubit state is known to Alice while the two-qubit state which is a non-maximally entangled Bell state is known to Candy. The three parties are connected through a single entangled state which acts as a quantum channel. We first describe the protocol in the ideal case when the entangled channel under use is in a pure state. After that, we consider the effect of amplitude damping(AD) noise on the quantum channel and describe the protocol executed through the noisy channel. The decrement of the fidelity is shown to occur with the increment in the noise parameter. This is shown by numerical computation in specific examples of the states to be created. Finally, we show that it is possible to maintain the label of fidelity to some extent and hence to decrease the effect of noise by the application of weak and reversal measurements. We also present a scheme for the generation of the five-qubit entangled resource which we require as a quantum channel. The generation scheme is run on the IBMQ platform.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.11174081,11034002,11104075,and 11134003)the National Basic Research Program of China (Grant Nos.2011CB921602 and 2012CB821302)the Open Fund from the SKLPS of ECNU
文摘Using two tripartite Greenberger-Horne-Zeilinger （GHZ） states as the shared channels, we investigate the noise effects on the deterministic joint remote preparation of an arbitrary two-qubit state. By unitary matrix decomposition procedure, we first construct the quantum logic circuit of the deterministic joint remote state preparation protocol. Then, we analytically derive the fidelity and the average fidelity for the deterministic joint remote preparation of an arbitrary two- qubit state and of four types of special two-qubit states under the influence of the Pauli noises. It is found that the fidelity depends on the noise types, the qubit-environment coupling strength, and the state to be remotely prepared. Moreover, even if the two GHZ channels are subject to the same environmental noises, the average fidelities for remotely preparing different two-qubit states display different time evolution behaviors. The remote preparation of the identical two-qubit states also shows that the average fidelities affected by different noisy environments exhibit different evolution actions.
基金National Natural Science Foundation of China under Grant Nos.60708003,60578050,and 10434060the State Key Basic Research Program of China under Grant No.2006CB921604+1 种基金the Shanghai Science and Technology Committee under Grant No.07JC14017the Director Fund of State Key Laboratory of Precision Spectroscopy
文摘Using a quantum channel consisting of a GHZ state exposed to noisy environment,we investigate how toremotely prepare an entangled state and a qubit state,respectively.By solving the master equation in the Lindbladform,the influence of the various types of noises on the GHZ state is first discussed.Then we use the fidelity to describehow close the remotely prepared state and the initial state are.Our results show that the fidelity is a function of thedecoherence rates and the angles of the initial state.It is found that for each of the two RSP schemes,the influence ofthe noise acting simultaneously in x,y,and z directions on the average fidelity is the strongest while the influence of thenoise acting in x or z direction on the average fidelity is relatively weaker.
基金supported by the National Natural Science Foundation of China (10874254)
文摘The radiation decay of a two-level atom could be inhibited within structured environments even under longtime evolution.We investigate the stabilized quantum coherence of composite systems undergoing local dissipation and exploit it further as a resource for remote state preparation.We focus on outputs of quantum states with solely quantum discord(i.e.,without entanglement)and demonstrate that they could be resulted from various initial states providing specific spectral structure of the reservoir.In detail,we elaborate the behavior of stabilized quantum discord and the corresponding fidelity for remote state preparation in connection with structural spectra of Ohmic class reservoir and of photonic band gap mediums.
文摘WITS-Math is a mathematical equation formatting tool in WITS, a multilingual document preparation environment. WITS-Math includes a library manager and an equation formatter. The main task of WITS-Math is to format diversities of mathematical equations and organize them into an equation library used by other tools in the WITS environment.WITS-Math is a direct manipulation mathematics editor. It uses syntax directed markup language as the internal representation, alld provides an interactive WYSIWYG interface for users to format equations. WITS-Math provides an equation access mechanism. Other tools can access equations in a library by cross-reference from a source file or through data exchange without knowillg the structure of equation libraries. The common data structure and the rendering object in the WITS platform ensure that the formatted equations can be directly used by other tools.
