Effects of classical random external field on the dynamics of entanglement in a four-qubit system  

作　　者：Edwige Carole Fosso Fridolin Tchangnwa Nya Lionel Tenemeza Kenfack Martin Tchoffo 

机构地区：[1]Research Unit of Condensed Matter,Electronic and Signal Processing,Department of Physics,Dschang School of Sciences and Technology,University of Dschang,PO Box:67 Dschang,Cameroon [2]Material Science Research Group,Physics Laboratory,Department of Physics,Post Graduate School,University of Maroua,PO Box:814 Maroua,Cameroon [3]Centre d’Etudes et de Recherches en Agronomie et en Biodiversite,Faculte d’Agronomie et des Sciences Agricoles,Universite de Dschang,Cameroun

出　　处：《Chinese Physics B》2021年第11期240-252,共13页中国物理B（英文版）

摘　　要：We investigate the dynamics of entanglement through negativity and witness operators in a system of four noninteracting qubits driven by a classical phase noisy laser characterized by a classical random external field(CREF).The qubits are initially prepared in the GHZ-type and W-type states and interact with the CREF in two different qubit-field configurations,namely,common environment and independent environments in which the cases of equal and different field phase probabilities are distinguished.We find that entanglement exhibits different decaying behavior,depending on the input states of the qubits,the qubit-field coupling configuration,and field phase probabilities.On the one hand,we demonstrate that the coupling of the qubits in a common environment is an alternative and more efficient strategy to completely shield the system from the detrimental impacts of the decoherence process induced by a CREF,independent of the input state and the field phase probabilities considered.Also,we show that GHZ-type states have strong dynamics under CREF as compared to W-type states.On the other hand,we demonstrate that in the model investigated the system robustness’s can be greatly improved by increasing the number of qubits constituting the system.

关 键 词：ENTANGLEMENT qubit and classical random external field 

分 类 号：O413[理学—理论物理]