papers

Publications (20)

quant-ph2006

Conversion of entanglement between continuous variable and qubit systems

Xiao-yu Chen, Liang-neng Wu, Li-zhen Jiang +1

We investigate how entanglement can be transferred between continuous variable and qubit systems. We find that a two-mode squeezed vacuum state and a continuous variable Werner sta…

quant-ph2013

Strong Coupling between a Topological Qubit and a Nanomechanical Resonator

Fang-Yu Hong, Huiqin Qian, Jing-Li Fu +2

We describe a scheme that enables a strong coherent coupling between a topological qubit and the quantized motion of a magnetized nanomechanical resonator. This coupling is achieve…

quant-ph2012

Realignment Entanglement Criterion for Continuous Bipartite Symmetric Quantum States

Xiao-yu Chen, Li-zhen Jiang, Ping Yu +1

The separability of bipartite non-Gaussian states is studied by applying the realignment criterion with the technique of functional analysis. The realignment criterion is given as…

quant-ph2006

Quantum state conversion between continuous variable and qubits systems

Xiao-yu Chen, Liang Han, Li-zhen Jiang

We investigate how quantum state can be converted between continuous variable and qubits systems. Non-linear Jaynes-Cumings interaction Hamiltonian is introduced to accomplish the…

quant-ph2005

Relative entropy of entanglement of a kind of two qubit entangled states

Xiao-yu Chen, Li-min Meng, Li-zhen Jiang +1

We in this paper strictly prove that some block diagonalizable two qubit entangled state with six none zero elements reaches its quantum relative entropy entanglement by the a sepa…

quant-ph2011

Entanglement bound for multipartite pure states based on local measurements

Li-zhen Jiang, Xiao-yu Chen, Tian-yu Ye

An entanglement bound based on local measurements is introduced for multipartite pure states. It is the upper bound of the geometric measure and the relative entropy of entanglemen…

quant-ph2018

Necessary and sufficient criterion for k-separability of N-qubit noisy GHZ states

Xiao-yu Chen, Li-zhen Jiang, Zhu-an Xu

A Multipartite entangled state has many different kinds of entanglement specified by the number of partitions. The most essential example of multipartite entanglement is the entang…

quant-ph2010

The coherent information of Pauli channels with coded inputs

Xiao-yu Chen, Li-zhen Jiang

The calculating of the coherent information is a fundamental step in obtaining the quantum capacity of a quantum channel. We introduce orthogonal and complete code basis to evaluat…

quant-ph2018

Precise detection of multipartite entanglement in four-qubit Greenberger--Horne--Zeilinger diagonal states

Xiao-yu Chen, Li-zhen Jiang, Zhu-an Xu

We propose a method of constructing the separability criteria for multipartite quantum states on the basis of entanglement witnesses. The entanglement witnesses are obtained by fin…

quant-ph2019

A hierarchy of entanglement criteria for four qubit symmetric Greenberger-Horne-Zeilinger diagonal states

Xiao-yu Chen, Li-zhen Jiang

With a two step optimization method of entanglement witness, we analytically propose a set of necessary and sufficient entanglement criteria for four qubit symmetric Greenberger-Ho…

quant-ph2003

Entanglement bounds for squeezed non-symmetric thermal state

Li-zhen Jiang

I study the three parameters bipartite quantum Gaussian state called squeezed asymmetric thermal state, calculate Gaussian entanglement of formation analytically and the up bound o…

quant-ph2012

Genuine Entanglement of Four Qubit Cluster Diagonal States

Xiao-yu Chen, Ping Yu, Li-zhen Jiang +1

We reduce the necessary and sufficient biseparable conditions of the four qubit cluster diagonal state to concise forms. Only 4 out of the 15 parameters are proved to be relevant i…

quant-ph2012

Entanglement Criterion for Coherent Subtraction and Coherent Addition Bipartite Continuous variable States

Li-zhen Jiang, Xiao-yu Chen, Tian-yu Ye +1

Photon subtraction and addition are experimental means of generating non-Gaussian states from Gaussian states. Coherent subtraction or addition is a combination of photon subtracti…

quant-ph2006

The entanglement of damped noon-state and its performance in phase measurement

Xiao-Yu Chen, Li-zhen Jiang, Liang Han

The state evolution of the initial optical \textit{noon} state is investigated. The residue entanglement of the state is calculated after it is damped by amplitude and phase dampin…

quant-ph2012

Entanglement and genuine entanglement of three qubit GHZ diagonal states

Xiao-yu Chen, Li-zhen Jiang, Ping Yu +1

We analytically prove the necessary and sufficient criterion for the full separability of three-qubit Greenberger-Horne-Zeilinger (GHZ) diagonal states. The corresponding entanglem…

quant-ph2009

The entanglement of some non-two-colorable graph states

Xiao-yu Chen, Li-zhen Jiang

We exactly evaluate the entanglement of a six vertex and a nine vertex graph states which correspond to non ''two-colorable'' graphs. The upper bound of entanglement for five verti…

quant-ph2006

Simultaneous amplification and non-symmetric amplitude damping of two-mode Gaussian state

Xiao-yu Chen, Li-zhen Jiang, Ji-wu Chen

The evolution of two-mode Gaussian state under symmetric amplification, non-symmetric damping and thermal noise is studied. The time dependent solution of the state characteristic…

quant-ph2012

A Robust Quantum Random Access Memory

Fang-Yu Hong, Yang Xiang, Zhi-Yan Zhu +2

A "bucket brigade" architecture for a quantum random memory of memory cells needs times of quantum manipulation on control circuit nodes per memory call. Here we…

quant-ph2011

Entanglement of stabilizer codewords

Xiao-yu Chen, Li-zhen Jiang

The geometric measure, the logarithmic robustness and the relative entropy of entanglement are proved to be equal for a stabilizer quantum codeword. The entanglement upper and lowe…

quant-ph2010

Graph state basis for Pauli Channels

Xiao-yu Chen, Li-zhen Jiang

We introduce graph state basis diagonalization to calculate the coherent information of a quantum code passing through a Pauli channel. The scheme is 5000 times faster than the bes…