Picosecond-long spin current generation along the low-symmetry axis of WTe<sub>2</sub>

Bulletin of the American Physical Society

Bulletin Home

APS March Meeting 2021

Volume 66, Number 1

Monday–Friday, March 15–19, 2021; Virtual; Time Zone: Central Daylight Time, USA

Session X52: Magnetic Topological Materials 8: New Materials

8:00 AM–11:00 AM, Friday, March 19, 2021

Sponsoring Units: DMP GMAG
Chair: Jonathan Gaudet, Johns Hopkins University

Abstract: X52.00001 : Picosecond-long spin current generation along the low-symmetry axis of WTe₂

8:00 AM–8:12 AM Live

Abstract

Presenter:

Kyusup Lee
(Department of Electrical and Computer Engineering, National University of Singapore)

Authors:

Kyusup Lee
(Department of Electrical and Computer Engineering, National University of Singapore)

Mengji Chen
(Department of Electrical and Computer Engineering, National University of Singapore)

Jie Li
(Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mould Technology, Huazhong University of Science and Technology)

Liang Cheng
(Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University)

Qisheng Wang
(Department of Electrical and Computer Engineering, National University of Singapore)

Kaiming Cai
(Department of Electrical and Computer Engineering, National University of Singapore)

Ee Min Elbert Chia
(Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University)

Haixin Chang
(Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mould Technology, Huazhong University of Science and Technology)

Hyunsoo Yang
(Department of Electrical and Computer Engineering, National University of Singapore)

Spin current generation and detection underlie modern spintronics. In particular, the spin current with an out-of-plane spin polarization can efficiently manipulate magnetic devices with perpendicular magnetic anisotropy. Weyl semimetal WTe₂ is of great potential in generating spin currents with an out-of-plane spin polarization due to intrinsic inversion symmetry breaking. Here we use an optical-driven terahertz (THz) emission spectroscopy and show a picosecond-long spin current generation along the rotational asymmetry a-axis of WTe₂ with the out-of-plane spin orientation. The underlying mechanism of the THz emission is the circular photogalvanic effect with a circularly polarized laser excitation, which is incident to the sample surface normal. The inversion symmetry breaking induces a spin-splitting band, enabling the manipulation of the spin current direction with opposite spin orientations depending on the helicity of the laser excitation. The temperature dependent study reveals that the CPGE vanishes at 175 K due to the carrier compensation. Our finding shows a great potential for the future development of THz spintronic devices with Weyl semimetals.

About APS

The American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics.

Headquarters 1 Physics Ellipse, College Park, MD 20740-3844 (301) 209-3200
Editorial Office 100 Motor Pkwy, Suite 110, Hauppauge, NY 11788 (631) 591-4000
Office of Public Affairs 529 14th St NW, Suite 1050, Washington, D.C. 20045-2001 (202) 662-8700

Bulletin of the American Physical Society

APS March Meeting 2021

Volume 66, Number 1

Monday–Friday, March 15–19, 2021; Virtual; Time Zone: Central Daylight Time, USA

Session X52: Magnetic Topological Materials 8: New Materials

Abstract: X52.00001 : Picosecond-long spin current generation along the low-symmetry axis of WTe2

Presenter:

Authors:

Follow Us

Engage

My APS

Information for

About APS

Abstract: X52.00001 : Picosecond-long spin current generation along the low-symmetry axis of WTe₂