Intrinsic Electric Field-Induced Properties in Janus MoSSe van der Waals Structures

Abstract

Focusing on two-dimensional (2D) Janus MoSSe monolayers, we show that simultaneously existing in-plane and out-of-plane intrinsic electric fields cause Zeeman-and Rashba-type spin splitting, respectively. In MoSSe van der Waals (vdW) structures, intrinsic electric field results in a large interlayer band offset. Therefore, large interlayer band offset, being the driving force for interlayer excitons, endows ultralong lifetimes to excitons and might dissociate excitons into free carriers. In comparison to its parent structure (i.e., MoS 2 ), MoSSe vdW structures are rather appealing for new concepts in light−electricity interconversion. In addition, the Rashba effects could be tuned by changing the interlayer distances due to the competition between the intralayer and interlayer electric field. Due to the large band offset, valley polarization relaxation is markedly reduced, promising enhanced valley polarization and ultralong valley lifetimes. As a result, MoSSe vdW structures harbor strong valley-contrasting physics, making them competitive systems to their parent structures.

Oxygenation‐Induced Two‐Dimensional Topological Insulators in Antimony Arsenide

“…Zeeman‐type spin splitting also occurs at K point. The similar situation was observed in MoSSe van der Waals structures, which are ascribed to intrinsic electric field . The strength of the Rashba spin splitting can be estimated by the Rashba parameters as described in ref.…”

An emerging Janus MoSeTe material for potential applications in optoelectronic devices

“…22 Another strategy to synthesize MoSSe starts from the CVD as-grown MoSe 2 monolayers on a SiO 2 /Si substrate, followed by sulfurization on the top layer Se in a controlled substitutional reaction with vaporized sulfur. 23 Based on ab initio calculations, the large Zeeman-and Rashba-type spin splitting and strong in-plane and vertical piezoelectric effects are systemically studied for Janus MXY (M = Mo, W, and X/Y = S, Se, and Te), [24][25][26] which makes a main contribution to light-electricity interconversion. Additionally, the structures and electronic properties of 2D TMD alloys with halfto-half mixing of S and Se for Sc, Ti, Cr, Mn, Fe, Zr, Mo and W were studied for the first time.…”

Enhanced electron–phonon scattering in Janus MoSSe

“…In addition, the vertical electric field also introduce piezoelectric effects, and can be tuned by strain [14]. The MoSSe based heterostructures exhibit unique electronic and optical properties and the Rashba SOI varies with the interlayer distances [15,16]. Moreover, the large band offset reduce the valley polarization dramatically and hence increase the valley lifetime of the heterostructures.…”

“…The carrier relaxation dynamics of several TMDs are investigated experimentally and theoretically [26][27][28][29][30], which mainly focus on the spin dependent e-ph interaction. Although synthesized successfully, Janus MoSSe structures have been studied mostly on the electronic structures [15,16]. In this paper, the e-ph interaction including scattering and lifetime of MoSSe are investigated in detail.…”