Modification of the electronic and spintronic properties of monolayer GaGeTe with a vertical electric field

Abstract

Development of two-dimensional (2D) nanoelectronics is appealing for electrically tunable properties in 2D materials. By means of density functional theory computations, we systematically study the modulation of vertical electric field on the electronic structure and spintronic properties of monolayer GaGeTe. A transition from indirect to direct bandgap is realized with an electric field of 0.11 V Å −1 . The direct bandgap monotonously diminishes due to the giant Stark effect with a Stark coefficient of 3.68 Å. A critical electric field of 0.43 V Å −1 is predicted, at which the semiconductor-to-metal transition occurs, and the effective mass of holes is correspondingly tuned to as low as 0.16 m 0 . Electric-field-induced SOC plays an important role in the spintronic properties of monolayer GaGeTe so that a widely tunable SOC splitting from 0 to 78.3 meV is achieved, and switchable spin-polarization features are also predicted in the spin texture. The spin splitting is attributed to the Rashba effect with the Rashaba contribution coefficients tuned from 0 eVÅ to 0.15 eVÅ. As the all-electrical control method is demonstrated, the physical mechanism related to the redistribution of the electronic states is further revealed. The outstanding electronic and transport features as well as the widely controllable spintronic properties of monolayer GaGeTe hold a great promise for their applications in the field of 2D nanoelectronics and spintronics.

T-Phase and H-Phase Coupled TMD van der Waals Heterostructure ZrS2/MoTe2 with Both Rashba Spin Splitting and Type-III Band Alignment

“…The application of an external electric field is widely used not only in theory but also in experiments to tune the electronic structure of 2D materials. − The effect of the external electric field on the electronic properties of the ZrS 2 /MoTe 2 heterostructure was investigated. Here, the direction of the positive electric field is designated as pointing from the ZrS 2 layer to the MoTe 2 layer.…”

A two-dimensional MoS2/C3N broken-gap heterostructure, a first principles study

“…26,49 The electric eld can be used to modulate the positions of VBM and CBM in 2D semiconductors, such as the CBM shis to low energy as an external electric eld applied perpendicular to the surface of GaGeTe monolayer. 50 The electric eld also can modify the band alignment of 2D heterostructures, 26,28 such as a type II band alignment transforms to type III one as an the electric eld is larger than 0.6 VÅ À1 in MoTe 2 /WSe 2 heterostructure. 51 The effects of external electric eld on the band alignment of MoS 2 /C 3 N heterostructure were investigated by decreases with the increase of negative electric eld and increases with the positive electric eld.…”

Structural, electronic, and transport properties of Janus XMoSiP2 ( X= S, Se, Te) monolayers: a first-principles study

“…Also, the charge redistribution in materials due to the applied external electric field can lead to changes in their electronic features. For example, previous studies indicated that the the band gaps of the group III monochalcogenides and their Janus structures depends strongly on the external electric fields [51][52][53]. Particularly, the transition from indirect to direct band gap is found in monolayer GaSe when the electric is applied [52].…”