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Title: Emerging materials and design principles for wurtzite-type ferroelectrics
Low-energy compute-in-memory architectures promise to reduce the energy demand for computation and data storage. Wurtzite- type ferroelectrics are promising options for both performance and integration with existing semiconductor processes. The Al1-xScxN alloy is among the few tetrahedral materials that exhibit polarization switching, but the electric field required to switch the polarization is too high (few MV/cm). Going beyond binary com- pounds, we explore the search space of multinary wurtzite-type compounds. Through this large-scale search, we identify four prom- ising ternary nitrides and oxides, including Mg2PN3, MgSiN2, Li2SiO3, and Li2GeO3, for future experimental realization and engi- neering. In >90% of the considered multinary materials, we identify unique switching pathways and non-polar structures that are distinct from the commonly assumed switching mechanism in AlN-based materials. Our results disprove the existing design principle based on the reduction of the wurtzite c/a lattice parameter ratio when comparing different chemistries while sup- porting two emerging design principles—ionicity and bond strength.  more » « less
Award ID(s):
2119281
NSF-PAR ID:
10502736
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Matter
Date Published:
Journal Name:
Matter
Volume:
7
Issue:
4
ISSN:
2590-2385
Page Range / eLocation ID:
1644 to 1659
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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