Enhancing von Neumann entropy by chaos in spin–orbit entanglement  

作　　者：Chen-Rong Liu Pei Yu Xian-Zhang Chen Hong-Ya Xu Liang Huang Ying-Cheng Lai 刘郴荣;喻佩;陈宪章;徐洪亚;黄亮;来颖诚(School of Physical Science and Technology,and Key Laboratory for Magnetism and Magnetic Materials of MOE,Lanzhou University,Lanzhou 730000,China;School of Electrical,Computer,and Energy Engineering,Arizona State University,Tempe,AZ 85287,USA;Department of Physics,Arizona State University,Tempe,AZ 85287,USA)

机构地区：[1]School of Physical Science and Technology,and Key Laboratory for Magnetism and Magnetic Materials of MOE,Lanzhou University,Lanzhou 730000,China [2]School of Electrical,Computer,and Energy Engineering,Arizona State University,Tempe,AZ 85287,USA [3]Department of Physics,Arizona State University,Tempe,AZ 85287,USA

出　　处：《Chinese Physics B》2019年第10期153-159,共7页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11775101 and 11422541);the US Office of Naval Research(Grant No.N00014-16-1-2828)

摘　　要：For a quantum system with multiple degrees of freedom or subspaces, loss of coherence in a certain subspace is intimately related to the enhancement of entanglement between this subspace and another one. We investigate intra-particle entanglement in two-dimensional mesoscopic systems, where an electron has both spin and orbital degrees of freedom and the interaction between them is enabled by Rashba type of spin-orbit coupling. The geometric shape of the scattering region can be adjusted to produce a continuous spectrum of classical dynamics with different degree of chaos. Focusing on the spin degree of freedom in the weak spin-orbit coupling regime, we find that classical chaos can significantly enhance spin-orbit entanglement at the expense of spin coherence. Our finding that classical chaos can be beneficial to intra-particle entanglement may have potential applications such as enhancing the bandwidth of quantum communications.For a quantum system with multiple degrees of freedom or subspaces, loss of coherence in a certain subspace is intimately related to the enhancement of entanglement between this subspace and another one. We investigate intra-particle entanglement in two-dimensional mesoscopic systems, where an electron has both spin and orbital degrees of freedom and the interaction between them is enabled by Rashba type of spin–orbit coupling. The geometric shape of the scattering region can be adjusted to produce a continuous spectrum of classical dynamics with different degree of chaos. Focusing on the spin degree of freedom in the weak spin–orbit coupling regime, we find that classical chaos can significantly enhance spin–orbit entanglement at the expense of spin coherence. Our finding that classical chaos can be beneficial to intra-particle entanglement may have potential applications such as enhancing the bandwidth of quantum communications.

关 键 词：SPIN-ORBIT ENTANGLEMENT CHAOS von NEUMANN entropy SPIN DECOHERENCE 

分 类 号：O4[理学—物理]