Opto-valleytronics in the 2D van der Waals heterostructure

Abstract

The development of information processing devices with minimum carbon emission is crucial in this information age. One of the approaches to tackle this challenge is by using valleys (local extremum points in the momentum space) to encode the information instead of charges. The valley information in some material such as monolayer transition metal dichalcogenide (TMD) can be controlled by using circularly polarized light. This opens a new field called opto-valleytronics. In this article, we first review the valley physics in monolayer TMD and two-dimensional (2D) heterostructure composed of monolayer TMD and other materials. Such 2D heterostructure has been shown to exhibit interesting phenomena such as interlayer exciton, magnetic proximity effect, and spin-orbit proximity effect, which is beneficial for opto-valleytronics application. We then review some of the optical valley control methods that have been used in the monolayer TMD and the 2D heterostructure. Finally, a summary and outlook of the 2D heterostructure opto-valleytronics are given.

Low-Dimensional In2Se3Compounds: From Material Preparations to Device Applications

“…One is vertical vdW heterostructures and another is lateral heterostructures. Numerous ways have been used to fabricate heterostructures, such as mechanical stacking and direct growth for the design of vertical heterostructures and optical writing or direct growth for lateral heterostructures. ,, …”

“…Numerous ways have been used to fabricate heterostructures, such as mechanical stacking and direct growth for the design of vertical heterostructures and optical writing or direct growth for lateral heterostructures. 35,53,173 For In 2 Se 3 , lateral phase heterostructures can be designed by optical writing and direct growth. The basic principle of optical writing for heterostructure preparation is that local heating on material surfaces makes local phase transformation occur to form heterojunctions.…”

Interlayer excitons in MoSe2/2D perovskite hybrid heterostructures – the interplay between charge and energy transfer

“…[9][10][11][12][13][14] In contrast to epitaxial semiconductors, the absence of lattice matching constraints permits the stacking of an almost unlimited combination of mono and few layer 2D crystals to form heterostructures with new exotic properties. [15][16][17][18][19] Moreover, with simple fabrication technology, [20][21][22] it is possible to obtain atomically sharp interfaces, and the close proximity of stacked layers. The band alignment of layers, together with their spacing, can easily be controlled by the appropriate selection of materials.…”

Novel C3B/SiC2 Heterobilayer: Electro‐Optical Properties Induced by Different Interlayer Coupling

“…In fact, 2D vdWs heterobilayers formed by vertically stacking different monolayers, can also provide novel properties and unique capabilities. [28][29][30][31][32] For example, a topological superconductivity has been observed in CrBr 3 -NbSe 2 heterobilayer synthesized by molecular-beam epitaxy method. [31] A ambipolar field-effect transistor based on MoS 2 /Rubrene heterobilayer can acquire well-balanced electron and hole mobilities of 1.27 and 0.36 cm 2 (V•s) −1 , respectively.…”