skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Topological insulators for the generation of electron beams

Abstract

Measurements of photo-yields from various topological insulators (TIs) in ultra-high vacuum were made. Marked differences in the photoelectric yield were found between the freshly in-vacuum cleaved and the atmosphere cleaved TI samples. The spectral dependence of their quantum efficiency (QE) was obtained in as-cleaved and cesiated TI samples. Inferred work functions ranging from 5 to 5.5 eV were found in all TI samples before cesiation, and they were lowered by ~0.5 eV after cesiation. At the ultraviolet wavelength of 268 nm, the QE of all samples is ~2 × 10 -7 before cesiation but improved to 10 -4–10 -3 after cesiation. In conclusion, knowledge of the QE has practical implication and can serve as a useful guide for the development of a spin-polarized electron source. However, the spin polarized nature of the photo-emitted electron remains yet to be explored.

Authors:
ORCiD logo [1];  [1];  [1];  [1];  [1];  [1]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1484887
Alternate Identifier(s):
OSTI ID: 1485255
Report Number(s):
BNL-209656-2018-JAAM; BNL-209669-2018-JAAM
Journal ID: ISSN 0003-6951
Grant/Contract Number:  
SC0012704; AC02-98CH10886
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Applied Physics Letters
Additional Journal Information:
Journal Volume: 113; Journal Issue: 23; Journal ID: ISSN 0003-6951
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS

Citation Formats

Tian, Y., Gu, G., Johnson, P., Rao, T., Tsang, T., and Wang, E. Topological insulators for the generation of electron beams. United States: N. p., 2018. Web. doi:10.1063/1.5052415.
Tian, Y., Gu, G., Johnson, P., Rao, T., Tsang, T., & Wang, E. Topological insulators for the generation of electron beams. United States. doi:10.1063/1.5052415.
Tian, Y., Gu, G., Johnson, P., Rao, T., Tsang, T., and Wang, E. Mon . "Topological insulators for the generation of electron beams". United States. doi:10.1063/1.5052415.
@article{osti_1484887,
title = {Topological insulators for the generation of electron beams},
author = {Tian, Y. and Gu, G. and Johnson, P. and Rao, T. and Tsang, T. and Wang, E.},
abstractNote = {Measurements of photo-yields from various topological insulators (TIs) in ultra-high vacuum were made. Marked differences in the photoelectric yield were found between the freshly in-vacuum cleaved and the atmosphere cleaved TI samples. The spectral dependence of their quantum efficiency (QE) was obtained in as-cleaved and cesiated TI samples. Inferred work functions ranging from 5 to 5.5 eV were found in all TI samples before cesiation, and they were lowered by ~0.5 eV after cesiation. At the ultraviolet wavelength of 268 nm, the QE of all samples is ~2 × 10-7 before cesiation but improved to 10-4–10-3 after cesiation. In conclusion, knowledge of the QE has practical implication and can serve as a useful guide for the development of a spin-polarized electron source. However, the spin polarized nature of the photo-emitted electron remains yet to be explored.},
doi = {10.1063/1.5052415},
journal = {Applied Physics Letters},
number = 23,
volume = 113,
place = {United States},
year = {Mon Dec 03 00:00:00 EST 2018},
month = {Mon Dec 03 00:00:00 EST 2018}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on December 3, 2019
Publisher's Version of Record

Save / Share:

Works referenced in this record:

Topological insulators in Bi2Se3, Bi2Te3 and Sb2Te3 with a single Dirac cone on the surface
journal, May 2009

  • Zhang, Haijun; Liu, Chao-Xing; Qi, Xiao-Liang
  • Nature Physics, Vol. 5, Issue 6, p. 438-442
  • DOI: 10.1038/nphys1270