相关论文: Magnetic Phases of Rare Earth Hexagonal Manganites
The magnetic phases of hexagonal perovskites RMnO_3 (R=Ho, Er, Tm, Yb, Sc, Y) are analysed using group theory and the Landau theory of phase transitions. The competition between various magnetic order parameters is discussed in the context…
The present work aims to describe, within a single phenomenological approach, the specific sequence of phase transitions observed in the rare-earth manganites RMnO3 at zero magnetic field. It is shown that a single integrated description of…
Hexagonal Dy(0.5)Y(0.5)MnO3, a multiferroic rare-earth manganite with geometrically frustrated antiferromagnetism, has been investigated with single-crystal neutron diffraction measurements. Below 3.4 K magnetic order is observed on both…
Interesting magnetic structure found experimentally in a series of manganites RMnO$_3$, where R is a rare earth, was explained, ostensibly, by Kimura et al, in terms of a classical Heisenberg model with an assumed set of exchange…
The complete irreducible co-representations of the paramagnetic space group provide a simple and direct path to explore the symmetry restrictions of magnetically driven ferroelectricity. The method consists of a straightforward…
The order parameters of the magnetic, charge and structural orders at half-doped manganites are identified. A corresponding Landau theory of the phase transitions is formulated. Many structural and thermodynamical behaviors are accounted…
The aim of this work is to unravel a basic microscopic picture behind complex magnetic properties of hexagonal manganites. For these purposes, we consider two characteristic compounds: YMnO3 and LuMnO3, which form different magnetic…
We report a study of magnetic dynamics in multiferroic hexagonal manganite HoMnO3 by far-infrared spectroscopy. Low-temperature magnetic excitation spectrum of HoMnO3 consists of magnetic-dipole transitions of Ho ions within the…
Rare-earth manganites are fascinating, because they display a wide variety of fundamental properties from magnetism to ferroelectricity, from colossal magnetoresistance to semi-metallicity, and because they can be used in a number of…
We use a combination of symmetry analysis, phenomenological modelling and first-principles density functional theory to explore the interplay between the magnetic ground state and the detailed atomic structure in the hexagonal rare-earth…
Hexagonal manganites REMnO3 (RE, rare earths) have attracted significant attention due to their potential applications as multiferroic materials and the intriguing physics associated with the topological defects. The two-dimensional (2D)…
We report a high-pressure study of orthorhombic rare-earth manganites AMnO3 using Raman scattering (for A = Pr, Nd, Sm, Eu, Tb and Dy) and synchrotron X-ray diffraction (for A = Pr, Sm, Eu, and Dy). In all cases, a structural and…
We present a theory of the magnetic rare-earth nickel boride-carbides (RENi$_2$B$_2$C, RE=Ho, Er, Tm). Large total angular momentum allows one to employ semiclassical approximation and reduce the problem to the four-positional clock model.…
We present an improved analysis of the phase transitions in rare earth superconductor using Ginzburg-Landau theory. Our work is based on the systematic study of critical field and superconducting order parameter in the presence of localized…
Charge-ordered rare earth manganites Nd0.5Ca0.5MnO3, La0.25Nd0.25Ca0.5MnO3, Pr0.7Ca0.3MnO3 and Pr0.6Ca0.4MnO3 are found to exhibit dielectric constant anomalies around the charge-ordering or the magnetic transition temperatures. Magnetic…
Magnetic rare earths R have been proven to have a significant effect on the multiferroic properties of the orthorhombic manganites RMnO3. A re-examination of previous results from synchrotron based x-ray scattering experiments suggests that…
The magnetic phase diagrams of RMnO3 (R = Er, Yb, Tm, Ho) are investigated up to 14 Tesla via magnetic and dielectric measurements. The stability range of the AFM order below the Neel temperature of the studied RMnO3 extends to far higher…
Ferroelectric materials possess a spontaneous electric polarization and may be utilized in various technological applications ranging from non-volatile memories to solar cells and light polarizers. Recently, hexagonal rare-earth manganites,…
The structural and magnetic properties of the hexagonal four-layer form of SrMnO$_3$ have been investigated by combining magnetization measurements, electron diffraction and high-resolution synchrotron X-ray and neutron powder diffraction.…
We study the existence of incommensurate phases in the phase diagram of the two orbital double exchange model coupled with Jahn-Teller phonons and with superexchange interactions. In agreement with experimental results, we find that undoped…