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Title: Semicircular Rashba arc spin polarizer

Abstract

In this work, we study the generation of spin polarized currents using curved arcs of finite widths, in which the Rashba spin orbit interaction (RSOI) is present. Compared to the 1-dimensional RSOI arcs with zero widths studied previously, the finite width presents charge carriers with another degree of freedom along the transverse width of the arc, in addition to the longitudinal degree of freedom along the circumference of the arc. The asymmetry in the transverse direction due to the difference in the inner and outer radii of the arc breaks the antisymmetry of the longitudinal spin z current in a straight RSOI segment. This property can be exploited to generate spin z polarized current output from the RSOI arc by a spin unpolarized current input. The sign of the spin current can be manipulated by varying the arc dimensions.

Authors:
 [1];  [2];  [1];  [3]
  1. NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117456 (Singapore)
  2. (Off Kent Ridge Crescent, NUS), Singapore 117608 (Singapore)
  3. Advanced Concepts and Nanotechnology, Data Storage Institute, DSI Building, 5 Engineering Drive 1 (Off Kent Ridge Crescent, NUS), Singapore 117608 (Singapore)
Publication Date:
OSTI Identifier:
22273797
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 17; Conference: 55. annual conference on magnetism and magnetic materials, Atlanta, GA (United States), 14-18 Nov 2010; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CHARGE CARRIERS; COMPARATIVE EVALUATIONS; DEGREES OF FREEDOM; ELECTRIC CURRENTS; L-S COUPLING; ONE-DIMENSIONAL CALCULATIONS; SPIN; SPIN ORIENTATION; WIDTH

Citation Formats

Bin Siu, Zhuo, E-mail: a0018876@nus.edu.sg, Advanced Concepts and Nanotechnology, Data Storage Institute, DSI Building, 5 Engineering Drive 1, Jalil, Mansoor B. A., and Ghee Tan, Seng. Semicircular Rashba arc spin polarizer. United States: N. p., 2014. Web. doi:10.1063/1.4866388.
Bin Siu, Zhuo, E-mail: a0018876@nus.edu.sg, Advanced Concepts and Nanotechnology, Data Storage Institute, DSI Building, 5 Engineering Drive 1, Jalil, Mansoor B. A., & Ghee Tan, Seng. Semicircular Rashba arc spin polarizer. United States. doi:10.1063/1.4866388.
Bin Siu, Zhuo, E-mail: a0018876@nus.edu.sg, Advanced Concepts and Nanotechnology, Data Storage Institute, DSI Building, 5 Engineering Drive 1, Jalil, Mansoor B. A., and Ghee Tan, Seng. 2014. "Semicircular Rashba arc spin polarizer". United States. doi:10.1063/1.4866388.
@article{osti_22273797,
title = {Semicircular Rashba arc spin polarizer},
author = {Bin Siu, Zhuo, E-mail: a0018876@nus.edu.sg and Advanced Concepts and Nanotechnology, Data Storage Institute, DSI Building, 5 Engineering Drive 1 and Jalil, Mansoor B. A. and Ghee Tan, Seng},
abstractNote = {In this work, we study the generation of spin polarized currents using curved arcs of finite widths, in which the Rashba spin orbit interaction (RSOI) is present. Compared to the 1-dimensional RSOI arcs with zero widths studied previously, the finite width presents charge carriers with another degree of freedom along the transverse width of the arc, in addition to the longitudinal degree of freedom along the circumference of the arc. The asymmetry in the transverse direction due to the difference in the inner and outer radii of the arc breaks the antisymmetry of the longitudinal spin z current in a straight RSOI segment. This property can be exploited to generate spin z polarized current output from the RSOI arc by a spin unpolarized current input. The sign of the spin current can be manipulated by varying the arc dimensions.},
doi = {10.1063/1.4866388},
journal = {Journal of Applied Physics},
number = 17,
volume = 115,
place = {United States},
year = 2014,
month = 5
}
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