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Chinese Physics B
Chin. Phys. B, 2019, Vol. 28(10): 100501    DOI: 10.1088/1674-1056/ab3dff
SPECIAL TOPIC—110th Anniversary of Lanzhou University Prev   Next  

Enhancing von Neumann entropy by chaos in spin-orbit entanglement
Chen-Rong Liu(刘郴荣)1, Pei Yu(喻佩)1, Xian-Zhang Chen(陈宪章)1, Hong-Ya Xu(徐洪亚)2, Liang Huang(黄亮)1, Ying-Cheng Lai(来颖诚)2,3
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
Abstract  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.
Keywords:  spin-orbit entanglement      chaos      von Neumann entropy      spin decoherence  
Received:  31 July 2019      Revised:  21 August 2019      Accepted manuscript online: 
PACS:  05.45.Mt (Quantum chaos; semiclassical methods)  
  71.15.Rf (Relativistic effects)  
  73.23.-b (Electronic transport in mesoscopic systems)  
Fund: Project supported by the National Natural Science Foundation of China (Grant Nos. 11775101 and 11422541) and the US Office of Naval Research (Grant No. N00014-16-1-2828).
Corresponding Authors:  Liang Huang     E-mail:  huangl@lzu.edu.cn

Cite this article: 

Chen-Rong Liu(刘郴荣), Pei Yu(喻佩), Xian-Zhang Chen(陈宪章), Hong-Ya Xu(徐洪亚), Liang Huang(黄亮), Ying-Cheng Lai(来颖诚) Enhancing von Neumann entropy by chaos in spin-orbit entanglement 2019 Chin. Phys. B 28 100501

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