Spin-orbital-lattice coupling and the phonon Zeeman effect in the Dirac honeycomb magnet CoTiO3

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F25%3A10508651" target="_blank" >RIV/00216208:11320/25:10508651 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=AoBM7.9Yg1" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=AoBM7.9Yg1</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevB.111.104419" target="_blank" >10.1103/PhysRevB.111.104419</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Spin-orbital-lattice coupling and the phonon Zeeman effect in the Dirac honeycomb magnet CoTiO3

Popis výsledku v původním jazyce

The entanglement of electronic spin and orbital degrees of freedom is often the precursor to emergent behaviors in condensed matter systems. With considerable spin-orbit coupling strength, the cobalt atom on a honeycomb lattice offers a platform that can make accessible the study of novel magnetic ground states. Using temperature-dependent Raman spectroscopy and high-magnetic-field Raman and IR spectroscopy, we studied the lattice and spin-orbital excitations in CoTiO(3), an antiferromagnetic material that exhibits topologically protected magnon Dirac crossings in the Brillouin zone. Under the application of an external magnetic field up to 22 T along the crystalline c axis, we observed the splitting of both the spin-orbital excitations and a phonon nearby in energy. Using density functional theory (DFT), we identify a number of modes that below the antiferromagnetic (AFM) transition become Raman active due to the zone folding of the Brillouin zone caused by the doubling of the magnetic unit cell. The phonon splitting under an applied magnetic field, or the phonon Zeeman effect, is observed in both a zone-centered phonon as well as its zone-folded counterpart. We use a model that includes both the spin and orbital degrees of freedom of the Co(2+) ions to explain the spin-orbital excitation energies and their behavior in an applied field. Our experimental observations along with several deviations from the model behavior point to significant coupling between the spin-orbital and the lattice excitations.

Název v anglickém jazyce

Spin-orbital-lattice coupling and the phonon Zeeman effect in the Dirac honeycomb magnet CoTiO3

Popis výsledku anglicky

The entanglement of electronic spin and orbital degrees of freedom is often the precursor to emergent behaviors in condensed matter systems. With considerable spin-orbit coupling strength, the cobalt atom on a honeycomb lattice offers a platform that can make accessible the study of novel magnetic ground states. Using temperature-dependent Raman spectroscopy and high-magnetic-field Raman and IR spectroscopy, we studied the lattice and spin-orbital excitations in CoTiO(3), an antiferromagnetic material that exhibits topologically protected magnon Dirac crossings in the Brillouin zone. Under the application of an external magnetic field up to 22 T along the crystalline c axis, we observed the splitting of both the spin-orbital excitations and a phonon nearby in energy. Using density functional theory (DFT), we identify a number of modes that below the antiferromagnetic (AFM) transition become Raman active due to the zone folding of the Brillouin zone caused by the doubling of the magnetic unit cell. The phonon splitting under an applied magnetic field, or the phonon Zeeman effect, is observed in both a zone-centered phonon as well as its zone-folded counterpart. We use a model that includes both the spin and orbital degrees of freedom of the Co(2+) ions to explain the spin-orbital excitation energies and their behavior in an applied field. Our experimental observations along with several deviations from the model behavior point to significant coupling between the spin-orbital and the lattice excitations.

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

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

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

10

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

9

Strana od-do

104419

Kód UT WoS článku

001457114900003

EID výsledku v databázi Scopus

2-s2.0-105000472750