Quantum paraelectricity and structural phase transitions in strontium titanate beyond density functional theory

Autor(en)

Carla Verdi, Luigi Ranalli, Cesare Franchini, Georg Kresse

Abstrakt

We demonstrate an approach for calculating temperature-dependent quantum and anharmonic effects with beyond density-functional theory accuracy. By combining machine-learned potentials and the stochastic self-consistent harmonic approximation, we investigate the cubic to tetragonal transition in strontium titanate and show that the paraelectric phase is stabilized by anharmonic quantum fluctuations. We find that a quantitative understanding of the quantum paraelectric behavior requires a higher-level treatment of electronic correlation effects via the random phase approximation. This approach enables detailed studies of emergent properties in strongly anharmonic materials beyond density-functional theory.

Organisation(en)

Computergestützte Materialphysik

Externe Organisation(en)

The University of Sydney, Università di Bologna, VASP Software GmbH

Journal

Physical Review Materials

Band

7

Anzahl der Seiten

6

ISSN

2475-9953

DOI

https://doi.org/10.48550/arXiv.2211.09616

Publikationsdatum

03-2023

Peer-reviewed

Ja

ÖFOS 2012

103018 Materialphysik, 103043 Computational Physics

ASJC Scopus Sachgebiete

Allgemeine Materialwissenschaften, Physics and Astronomy (miscellaneous)

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/705cbb90-a17d-4ac4-b562-50f88ec7c002