The emergence of two-dimensional Dirac materials, particularly transition metal dichalcogenides (TMDs), has reinvigorated interest in valleytronics, which utilizes the electronic valley degree of freedom for information storage and processing. Here, we review the basic valley-dependent properties and their experimental demonstrations in single-layer semiconductor TMDs with an emphasis on the effects of band topology and light–valley interactions. We also provide a brief summary of the recent advances on controlling the valley degree of freedom in TMDs with light and other means for potential applications.
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We acknowledge support from US Department of Energy (DOE) BES grant no. DESC0013883, Air Force Office of Scientific Research under grant FA9550-16-1-0249 and a David and Lucille Packard Fellowship and a Sloan Fellowship (K.F.M.); from DOE BES grant no. DE-SC0012509, National Science Foundation (NSF) grant no. EFRI-1433496, and a Cottrell Scholar Award (D.X.); and from NSF grant no. 1410407 and 1420451 (J.S.).
The authors declare no competing interests.
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Mak, K.F., Xiao, D. & Shan, J. Light–valley interactions in 2D semiconductors. Nature Photon 12, 451–460 (2018). https://doi.org/10.1038/s41566-018-0204-6
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