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arXiv · 2106.08783

Anharmonic stabilization of ferrielectricity in CuInP$_2$Se$_6$

Nikhil Sivadas·Peter Doak·P. Ganesh
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Abstract

Using first-principles calculations and group-theory based models, we study the stabilization of ferrielectricity (FiE) in CuInP$_2$Se$_6$. We find that the FiE ground state is stabilized by a large anharmonic coupling between the polar mode and a fully symmetric Raman-active mode. Our results open possibilities for controlling the single-step switching barrier for polarization by tuning the Raman-active mode. We discuss the implications of our findings in the context of designing next-generation optoelectronic devices that can overcome the voltage-time dilemma.

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Nikhil Sivadas, Peter Doak, P. Ganesh. 2021-06-16. Anharmonic stabilization of ferrielectricity in CuInP$_2$Se$_6$. https://doi.org/10.1103/physrevresearch.4.013094

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