Spin- and valley-coupled electronic states in monolayer WSe2 on bilayer graphene

被引：25

作者：

Sugawara, K. ^{[1
]}

Sato, T. ^{[2
]}

Tanaka, Y. ^{[2
]}

Souma, S. ^{[1
]}

Takahashi, T. ^{[1
,2
]}

机构：

[1] Tohoku Univ, Adv Inst Mat Res, WPI Res Ctr, Sendai, Miyagi 9808577, Japan

[2] Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan

来源：

APPLIED PHYSICS LETTERS | 2015年 / 107卷 / 07期

关键词：

MOS2; POLARIZATION; SEMICONDUCTOR; SYMMETRY;

D O I：

10.1063/1.4928658

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We have fabricated a high-quality monolayer WSe2 film on bilayer graphene by epitaxial growth and revealed the electronic states by spin- and angle-resolved photoemission spectroscopy. We observed a direct energy gap at the Brillouin-zone corner in contrast to the indirect nature of gap in bulk WSe2, which is attributed to the lack of interlayer interaction and the breaking of space-inversion symmetry in monolayer film. A giant spin splitting of similar to 0.5 eV, which is the largest among known monolayer transition-metal dichalcogenides, is observed in the energy band around the zone corner. The present results suggest a high potential applicability of WSe2 to develop advanced devices based with the coupling of spin-and valley-degrees of freedom. (C) 2015 AIP Publishing LLC.

引用

页数：4

共 25 条

[1] Observation of monolayer valence band spin-orbit effect and induced quantum well states in MoX2 [J].

Alidoust, Nasser ;

Bian, Guang ;

Xu, Su-Yang ;

Sankar, Raman ;

Neupane, Madhab ;

Liu, Chang ;

Belopolski, Ilya ;

Qu, Dong-Xia ;

Denlinger, Jonathan D. ;

Chou, Fang-Cheng ;

Hasan, M. Zahid .

NATURE COMMUNICATIONS, 2014, 5

[2]

BOcker Th., 2001, PHYS REV B, V64

[3]

Chhowalla M, 2013, NAT CHEM, V5, P263, DOI [10.1038/nchem.1589, 10.1038/NCHEM.1589]

[4] ELECTRONIC-STRUCTURE OF MOSE2, MOS2, AND WSE2 .1. BAND-STRUCTURE CALCULATIONS AND PHOTOELECTRON-SPECTROSCOPY [J].

COEHOORN, R ;

HAAS, C ;

DIJKSTRA, J ;

FLIPSE, CJF ;

DEGROOT, RA ;

WOLD, A .

PHYSICAL REVIEW B, 1987, 35 (12) :6195-6202

[5] ELECTRONIC ANALOG OF THE ELECTROOPTIC MODULATOR [J].

DATTA, S ;

DAS, B .

APPLIED PHYSICS LETTERS, 1990, 56 (07) :665-667

[6] Direct Measurement of the Thickness-Dependent Electronic Band Structure of MoS2 Using Angle-Resolved Photoemission Spectroscopy [J].

Jin, Wencan ;

Yeh, Po-Chun ;

Zaki, Nader ;

Zhang, Datong ;

Sadowski, Jerzy T. ;

Al-Mahboob, Abdullah ;

van der Zande, Arend M. ;

Chenet, Daniel A. ;

Dadap, Jerry I. ;

Herman, Irving P. ;

Sutter, Peter ;

Hone, James ;

Osgood, Richard M., Jr. .

PHYSICAL REVIEW LETTERS, 2013, 111 (10)

[7]

Mak KF, 2012, NAT NANOTECHNOL, V7, P494, DOI [10.1038/nnano.2012.96, 10.1038/NNANO.2012.96]

[8] BAND STRUCTURES OF TRANSITION-METAL-DICHALCOGENIDE LAYER COMPOUNDS [J].

MATTHEIS.LF .

PHYSICAL REVIEW B, 1973, 8 (08) :3719-3740

[9]

Pesin D, 2012, NAT MATER, V11, P409, DOI [10.1038/NMAT3305, 10.1038/nmat3305]

[10] Direct observation of spin-polarized bulk bands in an inversion-symmetric semiconductor [J].

Riley, J. M. ;

Mazzola, F. ;

Dendzik, M. ;

Michiardi, M. ;

Takayama, T. ;

Bawden, L. ;

Granerod, C. ;

Leandersson, M. ;

Balasubramanian, T. ;

Hoesch, M. ;

Kim, T. K. ;

Takagi, H. ;

Meevasana, W. ;

Hofmann, Ph ;

Bahramy, M. S. ;

Wells, J. W. ;

King, P. D. C. .

NATURE PHYSICS, 2014, 10 (11) :835-839

← 1 2 3 →