Magnetic polarons due to spin-length fluctuations in d4 spin-orbit Mott systems

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F25%3A00140141" target="_blank" >RIV/00216224:14310/25:00140141 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1103/PhysRevB.111.195125" target="_blank" >https://doi.org/10.1103/PhysRevB.111.195125</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevB.111.195125" target="_blank" >10.1103/PhysRevB.111.195125</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Magnetic polarons due to spin-length fluctuations in d4 spin-orbit Mott systems

Popis výsledku v původním jazyce

Mott insulators based on 4d and 5d transition-metal ions, where spin-orbit interaction plays a key role, can exhibit various forms of unusual magnetism. A particular example is the antiferromagnet Ca2RuO4 containing d4Ru4+ ions. Here the spin-orbit interaction stabilizes the nonmagnetic J=0 singlet ionic ground state, which gets dynamically mixed, via exchange interactions, with low-energy J=1 ionic excitations. Thanks to a sufficient strength of the exchange, these excitations condense and a long-range order emerges. The resulting ordered moments are soft and prone to fluctuations of their effective length. The corresponding amplitude mode appears as a prominent magnetic excitation and complements the conventional magnons involving rotations of the moments. Motivated by this peculiar kind of magnetic order and the specific spectrum of magnetic excitations, we study their influence on the propagation of doped carriers. To this end, we construct a microscopic model including both d4 and d5 degrees of freedom and address the propagation of an injected electron by employing self-consistent Born approximation. We find that the electron shows a combination of both free and a polaronic type of motion, where the mobile carrier strongly interacts with an accompanying cloud of magnetic excitations. Remarkably, in the latter case it is the exotic excitation, the amplitude mode, that is found to dominate over the contribution of magnons. Our soft-spin situation thus largely contrasts with spin polarons widely discussed in the context of doped Heisenberg-type magnets based on rigid spin moments.

Název v anglickém jazyce

Magnetic polarons due to spin-length fluctuations in d4 spin-orbit Mott systems

Popis výsledku anglicky

Mott insulators based on 4d and 5d transition-metal ions, where spin-orbit interaction plays a key role, can exhibit various forms of unusual magnetism. A particular example is the antiferromagnet Ca2RuO4 containing d4Ru4+ ions. Here the spin-orbit interaction stabilizes the nonmagnetic J=0 singlet ionic ground state, which gets dynamically mixed, via exchange interactions, with low-energy J=1 ionic excitations. Thanks to a sufficient strength of the exchange, these excitations condense and a long-range order emerges. The resulting ordered moments are soft and prone to fluctuations of their effective length. The corresponding amplitude mode appears as a prominent magnetic excitation and complements the conventional magnons involving rotations of the moments. Motivated by this peculiar kind of magnetic order and the specific spectrum of magnetic excitations, we study their influence on the propagation of doped carriers. To this end, we construct a microscopic model including both d4 and d5 degrees of freedom and address the propagation of an injected electron by employing self-consistent Born approximation. We find that the electron shows a combination of both free and a polaronic type of motion, where the mobile carrier strongly interacts with an accompanying cloud of magnetic excitations. Remarkably, in the latter case it is the exotic excitation, the amplitude mode, that is found to dominate over the contribution of magnons. Our soft-spin situation thus largely contrasts with spin polarons widely discussed in the context of doped Heisenberg-type magnets based on rigid spin moments.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

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

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2025

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

111

Číslo periodika v rámci svazku

19

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

20

Strana od-do

195125

Kód UT WoS článku

001495020000003

EID výsledku v databázi Scopus

2-s2.0-105005405107