Digital discovery of distorted-P1 molybdenum ditelluride and its significance in resistive switching

Abstract

We investigate the intricate polymorphism of 2D molybdenum ditelluride to unveil the elusive distorted metallic phase, which manifests intriguing non-volatile resistive switching. Employing an evolutionary ab initio structure search, we generate 1600 crystal structures and discover 14 unrecognized low-energy polymorphs, including a distorted metallic phase with P1 group symmetry, designated as DP1. This phase closely resembles the previously observed Hd phase in its diffraction pattern, yet it stands out due to its stability and distinct properties. Our comprehensive variable-cell nudged elastic band calculations reveal that the transition from the semiconducting hexagonal phase to DP1 is non-volatile, with charge doping capable of modulating the SET and RESET barriers. Additionally, phonon dispersion analysis and molecular dynamics simulations confirm DP1’s dynamic and structural resilience. Key findings of our study demonstrate that DP1 serves not as a transient, but as a stable, standalone phase with profound implications for memristor technology.