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Abstract Ferro-rotational magnet RbFe(SO4)2has attracted attention for its stable ferro-rotational phase and electric-field-controlled magnetic chirality. This work presents the multiferroic properties andH–Tphase diagram of RbFe(SO4)2, which have been underexplored. Our measurements of magnetic susceptibility, ferroelectric polarization, and dielectric constant under various magnetic fields reveal four distinct phases: (I) a ferroelectric and helical magnetic phase below 4 K and 6 T, (II) a paraelectric and collinear magnetic phase below 4 K and above 6 T, (III) a paraelectric and non-collinear magnetic phase below 4 K and above 9 T, and (IV) a paraelectric and paramagnetic above 4 K. This study clarifies the multiferroic behavior andH–Tphase diagram of RbFe(SO4)2, providing valuable insights into ferro-rotational magnets.
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Strain‐Driven Stabilization of a Room‐Temperature Chiral Multiferroic with Coupled Ferroaxial and Ferroelectric Order
Abstract Noncollinear ferroic materials are sought after as testbeds to explore the intimate connections between topology and symmetry, which result in electronic, optical, and magnetic functionalities not observed in collinear ferroic materials. For example, ferroaxial materials have rotational structural distortions that break mirror symmetry and induce chirality. When ferroaxial order is coupled with ferroelectricity arising from a broken inversion symmetry, it offers the prospect of electric‐field‐control of the ferroaxial distortions and opens up new tunable functionalities. However, chiral multiferroics, especially ones stable at room temperature, are rare. A strain‐stabilized, room‐temperature chiral multiferroic phase in single crystals of BaTiS3is reported here. Using first‐principles calculations, the stabilization of this multiferroic phase havingP63space group for biaxial tensile strains exceeding 1.5% applied on the basalab‐plane of the room temperatureP63cmphase of BaTiS3is predicted. The chiral multiferroic phase is characterized by rotational distortions of TiS6octahedra around the longc‐axis and polar displacement of Ti atoms along thec‐axis. The ferroaxial and ferroelectric distortions and their domains inP63‐BaTiS3are directly resolved using atomic resolution scanning transmission electron microscopy. Landau‐based phenomenological modeling predicts a strong coupling between the ferroelectric and the ferroaxial order makingP63‐BaTiS3an attractive test bed for achieving electric‐field‐control of chirality.
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- PAR ID:
- 10582401
- Publisher / Repository:
- arXiv
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 35
- Issue:
- 10
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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