Piezotronic Effect on Rashba Spin-Orbit Coupling in a ZnO/P3HT Nanowire Array Structure

Laipan Zhu; Yan Zhang; Pei Lin; Ying Wang; Leijing Yang; Libo Chen; Longfei Wang; Baodong Chen; Zhong Lin Wang

doi:10.1021/acsnano.7b08618

Piezotronic Effect on Rashba Spin-Orbit Coupling in a ZnO/P3HT Nanowire Array Structure

ACS Nano. 2018 Feb 27;12(2):1811-1820. doi: 10.1021/acsnano.7b08618. Epub 2018 Jan 24.

Authors

Laipan Zhu^{1

2}, Yan Zhang^{1

2

3}, Pei Lin^{1

2}, Ying Wang^{1

2}, Leijing Yang^{1

2}, Libo Chen^{1

2}, Longfei Wang^{1

2}, Baodong Chen^{1

2}, Zhong Lin Wang^{1

2

4}

Affiliations

¹ CAS Center for Excellence in Nanoscience, Beijing Key Laboratory of Micro-nano Energy and Sensor, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
² School of Nanoscience and Technology, University of Chinese Academy of Sciences , Beijing 100049, China.
³ School of Physical Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China.
⁴ School of Material Science and Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.

PMID: 29357222
DOI: 10.1021/acsnano.7b08618

Abstract

A key concept in the emerging field of spintronics is the voltage-gate control of spin precession via the effective magnetic field generated by the Rashba spin-orbit coupling (SOC). Traditional external gate voltage usually needs a power supply, which can easily bring about background noise or lead to a short circuit in measurement, especially for nanoscale spintronic devices. Here, we present a study on the circular photogalvanic effect (CPGE) in a ZnO/P3HT nanowire array structure with the device excited under oblique incidence. We demonstrate that a strong Rashba SOC is induced by the structure inversion asymmetry of the ZnO/P3HT heterointerface. We show that the Rashba SOC can be effectively tuned by inner-crystal piezo-potential created inside the ZnO nanowires instead of an externally applied voltage. The piezo-potential can not only ensure the stability of future spin-devices under a static pressure or strain but also work without the need of extra energy; hence this room-temperature generation and piezotronic effect control of spin photocurrent demonstrate a potential application in large-scale flexible spintronics in piezoelectric nanowire systems.

Keywords: Rashba spin−orbit coupling (SOC); ZnO nanowire array; circular photogalvanic effect (CPGE); piezo-potential; piezotronic effect.

Publication types

Research Support, Non-U.S. Gov't