|About this Abstract
||Materials Science & Technology 2019
||Ceramics and Glasses Simulations and Machine Learning
||Tuning Electronic Properties in II-IV-V2 Semiconductors via Sub-lattice Configurational Disorder
||Jacob Cordell, Jie Pan, Stephan Lany, Garritt J Tucker
|On-Site Speaker (Planned)
Multinary semiconductors have attracted interest recently for use in diverse energy conversion technologies. Order-dependent II-IV-V2 materials show promise as a means of achieving specific band gaps with lattice parameters matched to their analogue III-Vs. Structure-synthesis-property relationships for these materials are not well understood and computational techniques are sought to reveal the underlying physics of these materials. We investigated the ZnSnN2 and ZnGeN2 systems using Model Hamiltonian-based Monte Carlo simulations to create structures with different degrees of disorder related to occupation of cation sites. Formation energies and electronic structures were estimated from first principles calculations. A motif-Hamiltonian captures the energetics of the ZnSnN2 system in the Monte Carlo simulation while, for the ZnGeN2 system, a cluster expansion is needed to capture long-range ordering effects. This approach shows the stability of structures with varying degrees of disorder associated with effective temperatures for understanding properties of ZnSnN2 and ZnGeN2 grown under non-equilibrium conditions.