Nature of magnetic phase transitions and spin-driven ferroelectricity in BaHoFeO4

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F25%3A10508731" target="_blank" >RIV/00216208:11320/25:10508731 - isvavai.cz</a>

Result on the web

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=0Nvp6VGsPH" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=0Nvp6VGsPH</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/xz8c-3fp3" target="_blank" >10.1103/xz8c-3fp3</a>

Result language

angličtina

Original language name

Nature of magnetic phase transitions and spin-driven ferroelectricity in BaHoFeO4

Original language description

BaHoFeO4 is an emergent multiferroic material that exhibits unique magnetic-field (H)-induced ferroelectric behavior. However, the origin of this effect has remained elusive, due to the role of complex magnetic interactions in driving the system&apos;s behavior. To shed light on this, we investigated the magnetic structures of the material using neutron powder diffraction, as well as their magnetic-field-induced evolutions through a combination of complementary techniques, including magnetic measurements, M &amp; ouml;ssbauer spectroscopy, and terahertz time-domain spectroscopy. The orthorhombic crystal structure of the compound, characterized by the structural interconnection between two-dimensional Fe chains and Ho chains, remains stable upon cooling to 3 K. Below TN1 50 K, Fe3+ spins form a collinear incommensurate spin-density-wave antiferromagnetic order with a magnetic propagation vector k1 = (0, 0, 0.329), and the magnetic moments align along the b axis. Upon further cooling, the enhancement of the 3d-4f exchange coupling induces long-range order in the Ho sublattice below 25 K, transforming the magnetic structure into a noncollinear commensurate antiferromagnetic order with k2 = (0.5, 0, 0.5), with all Fe and Ho moments lying in the ac plane. As the temperature decreases further, strengthening of the 4 f-4 f interactions leads to the emergence of a new commensurate antiferromagnetic order with a magnetic propagation vector k3 = (0, 0, 0.5) at 3 K, coexisting with the antiferromagnetic structure associated with k2. Similar to the incommensurate spin-density-wave structure, the Ho and Fe spins in the k3 phase are oriented along the b axis, with their magnetic moments modulated along the c axis. The spin configuration of the Ho rings is highly sensitive to temperature and magnetic field, in contrast to the more robust spin configuration of the Fe rings. We attribute the H-induced magnetic and ferroelectric transitions in BaHoFeO4 to the H-induced modifications in the Ho sublattice. Two metamagnetic phase transitions occur at H1 1 T and H2 2 T, associated with a spin-flop transition of the Ho magnetic sublattice. The H-induced canted magnetic configuration in the Ho rings above H1 drives the H-induced ferroelectricity in BaHoFeO4. This is subsequently suppressed by the growth of a higher-field paraelectric antiferromagnetic phase, characterized by a fully ferromagnetic arrangement of the Ho chains above H2. Our study provides important insights into the origins of the metamagnetic phase transitions and the associated magnetoelectric effects.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

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

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

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

Publication year

2025

Confidentiality

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

Name of the periodical

Physical Review B

ISSN

2469-9950

e-ISSN

2469-9969

Volume of the periodical

112

Issue of the periodical within the volume

5

Country of publishing house

US - UNITED STATES

Number of pages

15

Pages from-to

054437

UT code for WoS article

001553595000001

EID of the result in the Scopus database

2-s2.0-105020907667