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Title: Spin-resolved photoemission study of epitaxially grown MoSe 2 and WSe 2 thin films

Abstract

Few-layer thick MoSe 2 and WSe 2 possess non-trivial spin textures with sizable spin splitting due to the inversion symmetry breaking embedded in the crystal structure and strong spin–orbit coupling. Here, we report a spin-resolved photoemission study of MoSe 2 and WSe 2 thin film samples epitaxially grown on a bilayer graphene substrate. Furthermore, we only found spin polarization in the single- and trilayer samples—not in the bilayer sample—mostly along the out-of-plane direction of the sample surface. The measured spin polarization is found to be strongly dependent on the light polarization as well as the measurement geometry, which reveals intricate coupling between the spin and orbital degrees of freedom in this class of material.

Authors:
 [1];  [2];  [3];  [4];  [4];  [4];  [5];  [1]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source
  2. Pusan National Univ., Busan (Korea, Republic of). Dept. of Physics
  3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source; Nanjing Univ. (China). National Lab. of Solid State Microstructures; SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Inst. of Materials and Energy Sciences
  4. Ecole Polytechnique Federale Lausanne (Switzlerland). Inst. of Physics; Paul Scherrer Inst. (PSI), Villigen (Switzerland). Swiss Light Source
  5. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Inst. of Materials and Energy Sciences; Stanford Univ., CA (United States). Geballe Lab. for Advaned Materials
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1349089
Grant/Contract Number:
AC02-05CH11231; AC02-76SF00515; 2015R1C1A1A01053065; PP00P2 144742/1
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Physics. Condensed Matter
Additional Journal Information:
Journal Volume: 28; Journal Issue: 45; Journal ID: ISSN 0953-8984
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; transition metal dichalcogenides; MoSe2; WSe2; spin-resolved photoemission; ARPEs; photoemission

Citation Formats

Mo, Sung-Kwan, Hwang, Choongyu, Zhang, Yi, Fanciulli, Mauro, Muff, Stefan, Hugo Dil, J., Shen, Zhi-Xun, and Hussain, Zahid. Spin-resolved photoemission study of epitaxially grown MoSe 2 and WSe 2 thin films. United States: N. p., 2016. Web. doi:10.1088/0953-8984/28/45/454001.
Mo, Sung-Kwan, Hwang, Choongyu, Zhang, Yi, Fanciulli, Mauro, Muff, Stefan, Hugo Dil, J., Shen, Zhi-Xun, & Hussain, Zahid. Spin-resolved photoemission study of epitaxially grown MoSe 2 and WSe 2 thin films. United States. doi:10.1088/0953-8984/28/45/454001.
Mo, Sung-Kwan, Hwang, Choongyu, Zhang, Yi, Fanciulli, Mauro, Muff, Stefan, Hugo Dil, J., Shen, Zhi-Xun, and Hussain, Zahid. 2016. "Spin-resolved photoemission study of epitaxially grown MoSe 2 and WSe 2 thin films". United States. doi:10.1088/0953-8984/28/45/454001. https://www.osti.gov/servlets/purl/1349089.
@article{osti_1349089,
title = {Spin-resolved photoemission study of epitaxially grown MoSe 2 and WSe 2 thin films},
author = {Mo, Sung-Kwan and Hwang, Choongyu and Zhang, Yi and Fanciulli, Mauro and Muff, Stefan and Hugo Dil, J. and Shen, Zhi-Xun and Hussain, Zahid},
abstractNote = {Few-layer thick MoSe2 and WSe2 possess non-trivial spin textures with sizable spin splitting due to the inversion symmetry breaking embedded in the crystal structure and strong spin–orbit coupling. Here, we report a spin-resolved photoemission study of MoSe2 and WSe2 thin film samples epitaxially grown on a bilayer graphene substrate. Furthermore, we only found spin polarization in the single- and trilayer samples—not in the bilayer sample—mostly along the out-of-plane direction of the sample surface. The measured spin polarization is found to be strongly dependent on the light polarization as well as the measurement geometry, which reveals intricate coupling between the spin and orbital degrees of freedom in this class of material.},
doi = {10.1088/0953-8984/28/45/454001},
journal = {Journal of Physics. Condensed Matter},
number = 45,
volume = 28,
place = {United States},
year = 2016,
month = 9
}

Journal Article:
Free Publicly Available Full Text
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