Robust spin-valley polarization in commensurate Mo S2 /graphene heterostructures

Qingming Zhang, Luojun Du, Qian Zhang, Benchao Gong, Mengzhou Liao, Jianqi Zhu, Hua Yu, Rui He, Kai Liu, Rong Yang, Dongxia Shi, Lin Gu, Feng Yan, Guangyu Zhang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

21 Citations (Scopus)

Abstract

The investigation and control of quantum degrees of freedom (DoFs) of carriers lie at the heart of condensed-matter physics and next-generation electronics/optoelectronics. van der Waals heterostructures stacked from distinct two-dimensional (2D) crystals offer an unprecedented platform for combining the superior properties of individual 2D materials and manipulating spin, layer, and valley DoFs. MoS2/graphene heterostructures, harboring prominent spin-transport properties of graphene, giant spin-orbit coupling, and spin-valley polarization of MoS2, are predicted as a perfect venue for optospintronics. Here, we report the epitaxial growth of commensurate MoS2 on graphene with high quality by chemical vapor deposition, and demonstrate robust temperature-independent spin-valley polarization at off-resonant excitation. We further show that the helicity of B exciton is larger than that of A exciton, allowing the manipulation of spin bits in the commensurate heterostructures by both optical helicity and wavelength. Our results open a window for controlling spin DoF by light and pave a way for taking spin qubits as information carriers in the next-generation valley-controlled optospintronics.
Original languageEnglish
Article number115445
JournalPhysical Review B
Volume97
Issue number11
DOIs
Publication statusPublished - 27 Mar 2018

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

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