Two-Dimensional Octuple-Atomic-Layer M2Si2N4 (M = Al, Ga and In) with Long Carrier Lifetime

Abstract

Bulk III-nitride materials MN (M = Al, Ga and In) and their alloys have been widely used in high-power electronic and optoelectronic devices, but stable two-dimensional (2D) III-nitride materials, except h-BN, have not been realized yet. A new kind of 2D III-nitride material M2Si2N4 (M = Al, Ga and In) is predicted by choosing Si as the appropriate passivation element. The stability, electronic and optical properties of 2D M2Si2N4 materials are studied systematically based on first-principles calculations. The results show that Al2Si2N4 and Ga2Si2N4 are found to be indirect bandgap semiconductors, while In2Si2N4 is a direct bandgap semiconductor. Moreover, Al2Si2N4 and In2Si2N4 have good absorption ability in the visible light region, while Ga2Si2N4 is an ultraviolet-light-absorbing material. Furthermore, the carrier lifetimes of Ga2Si2N4 and In2Si2N4 are as large as 157.89 and 103.99 ns, respectively. All these desirable properties of M2Si2N4 materials make them attractive for applications in electronics and photoelectronics.

AI‐Based Metamaterial Design for Wearables

“…Furthermore, metamaterials have already been used to enable grasping motions for different objects through mechanical metamaterial sensing, improve user comfort with auxetic metamaterials, and develop artificial skin sensation pathways composed of tactile sensors. [ 101–103 ] These functionalities can be improved further using more optimized metamaterial‐based sensors and facilitate fully‐functional neural interfaces for prosthetics. In addition to NICU‐specific applications, hearing aids, and assistive robotics, AI‐based metamaterial design can also improve applications in personalized medicine.…”