Anharmonicity of the antiferrodistortive soft mode in barium zirconate BaZrO3

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F23%3A00574090" target="_blank" >RIV/68378271:_____/23:00574090 - isvavai.cz</a>

Výsledek na webu

<a href="https://hdl.handle.net/11104/0344448" target="_blank" >https://hdl.handle.net/11104/0344448</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevB.108.014309" target="_blank" >10.1103/PhysRevB.108.014309</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Anharmonicity of the antiferrodistortive soft mode in barium zirconate BaZrO3

Popis výsledku v původním jazyce

Barium zirconate (BaZrO3) is one of the very few perovskites that is claimed to retain an average cubic structure down to 0K, while being energetically very close to an antiferrodistortive phase obtained by condensation of a soft phonon mode at the R point of the Brillouin zone boundary. In this work, we report a combined experimental and theoretical study of the temperature dependence of this soft phonon mode. Inelastic neutron and x-ray scattering measurements on single crystals show that it softens substantially from 9.4meV at room temperature to 5.6meV at 2K. In contrast, the acoustic mode at the same R point is nearly temperature independent. The effect of the anharmonicity on the lattice dynamics is investigated nonperturbatively using direct dynamic simulations as well as a first-principles-based self-consistent phonon theory, including quantum fluctuations of the atomic motion.n

Název v anglickém jazyce

Anharmonicity of the antiferrodistortive soft mode in barium zirconate BaZrO3

Popis výsledku anglicky

Barium zirconate (BaZrO3) is one of the very few perovskites that is claimed to retain an average cubic structure down to 0K, while being energetically very close to an antiferrodistortive phase obtained by condensation of a soft phonon mode at the R point of the Brillouin zone boundary. In this work, we report a combined experimental and theoretical study of the temperature dependence of this soft phonon mode. Inelastic neutron and x-ray scattering measurements on single crystals show that it softens substantially from 9.4meV at room temperature to 5.6meV at 2K. In contrast, the acoustic mode at the same R point is nearly temperature independent. The effect of the anharmonicity on the lattice dynamics is investigated nonperturbatively using direct dynamic simulations as well as a first-principles-based self-consistent phonon theory, including quantum fluctuations of the atomic motion.n

Druh

J_SC - Článek v periodiku v databázi SCOPUS

CEP obor

—

OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

<a href="/cs/project/EF16_019%2F0000760" target="_blank" >EF16_019/0000760: Fyzika pevných látek pro 21. století</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Physical Review B

ISSN

2469-9950

e-ISSN

2469-9969

Svazek periodika

108

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

13

Strana od-do

014309

Kód UT WoS článku

—

EID výsledku v databázi Scopus

2-s2.0-85166969074