Current-induced spin polarization method for detecting hexagonal warping of Bi2Te3 surface state

A technology of spin polarization and surface state, applied in the field of spintronics, can solve problems such as current-induced spin polarization separation of difficult three-dimensional topological insulators, and achieve the effects of low cost, strong practicability and broad application prospects.

Active Publication Date: 2021-09-21
FUZHOU UNIV
View PDF15 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, both approaches struggle to isolate the current-induced spin polarization of the hexagonal warping of the surface states of 3D topological insulators

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Current-induced spin polarization method for detecting hexagonal warping of Bi2Te3 surface state
  • Current-induced spin polarization method for detecting hexagonal warping of Bi2Te3 surface state
  • Current-induced spin polarization method for detecting hexagonal warping of Bi2Te3 surface state

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0041] The technical solution of the present invention will be specifically described below in conjunction with the accompanying drawings.

[0042] The present invention provides a detection Bi 2 Te 3 A method of current-induced spin polarization of surface state hexagonal warping, as figure 1 shown, including the following steps:

[0043] Step S1, growing three-dimensional topological insulator Bi on a suitable substrate 2 Te 3 Thin film, the thickness of the film is between a few nanometers and tens of nanometers;

[0044] The substrate used in this embodiment is the Si substrate of (111) crystal plane, adopting molecular beam epitaxy technology, the growth thickness is respectively the three-dimensional topological insulator Bi of 3nm, 7nm, 20nm 2 Te 3 film.

[0045] Step S2, in the three-dimensional topological insulator Bi 2 Te 3 Prepare a pair of rectangular electrodes on the film;

[0046] The electrodes prepared in this example are titanium gold electrodes: t...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a current-induced spin polarization method of hexagonal warping of a Bi2Te3 surface state. The method comprises the following steps: preparing a Bi2Te3 film sample and depositing a rectangular electrode on the Bi2Te3 film sample; connecting the electrode with the input end of the current preamplifier through a lead; respectively using the chopping frequency of the chopper and the frequency doubled by the photoelastic modulator as reference signals of the lock-in amplifier 1 and the lock-in amplifier 2, wherein the output end of the current preamplifier is connected with the input ends of the lock-in amplifier 1 and the lock-in amplifier 2; enabling light emitted by the laser to sequentially pass through the chopper, the polarizer, the photoelastic modulator and the lens, and irradiate the midpoint of a connecting line of the two electrodes on the sample at an incident angle theta; measuring common photoconductive current and circular polarization related photocurrent under different incident angles; and calculating to obtain circularly polarized light conductivity differential current under different incident angles, and fitting through a formula to obtain a change curve of the circularly polarized light conductivity differential current of the Bi2Te3 surface state hexagonal warping along with the incident angles.

Description

technical field [0001] The invention belongs to the field of spintronics, in particular to a method for detecting Bi 2 Te 3 A Current-Induced Spin Polarization Method for Hexagonal Warping of Surface States. Background technique [0002] The surface states of three-dimensional topological insulators are spin-momentum-locked Dirac-type electronic states, protected by time-reversal symmetry, and have good application prospects in the field of spintronic devices. Three-dimensional topological insulator Bi 2 Te 3 It is a typical third-generation three-dimensional topological insulator, so it has received extensive attention. Due to defects in the film growth process, the three-dimensional topological insulator Bi 2 Te 3 It is n-type conduction. When the concentration of electrons is large, the Fermi level will enter the conduction band. At this time, the spin directions of the electrons on the Fermi surface are not all in the plane, but a hexagonal warping phenomenon wil...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01R33/12
CPCG01R33/12
Inventor 俞金玲庄航程树英赖云锋郑巧
Owner FUZHOU UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap