相关论文: Ordering/displacive ferrielectricity in 2D CuInP$_…
We investigate the highly frustrated spin and orbital superexchange interactions in cubic vanadates. The fluctuations of $t_{2g}$ orbitals trigger a {\it novel mechanism of ferromagnetic interactions} between spins S=1 of V$^{3+}$ ions…
We report $\alpha$-Cu$_2$V$_2$O$_7$ to be an improper multiferroic with the simultaneous development of electric polarization and magnetization below $T_C$ = 35 K. The observed spontaneous polarization of magnitude 0.55 $\mu$Ccm$^{-2}$ is…
CuInP2S6 (CIPS) is an emerging layered material that exhibits ferrielectric ordering well above room temperature (Curie temperature TC ~ 315 K). When synthesized with Cu deficiencies, CIPS spontaneously segregates into CuInP2S6 and…
In order to explore the properties of a two-sublattice ferroelectric, we measured the infrared and Raman scattering response of CuInP2S6 across the ferroelectric and glassy transitions and compared our findings to a symmetry analysis,…
By means of first-principles simulations, we unambiguously show that improper ferroelectricity in magnetite in the low-temperature insulating phase is driven by charge-ordering. An accurate comparison between monoclinic ferroelectric Cc and…
Structural properties of CuAl$_{2}$O$_{4}$, which was recently argued to show unusual suppression of the Jahn-Teller distortions by the spin-orbit coupling, are investigated under pressures up to 6 GPa. Analysis of X-ray powder diffraction…
The fascinating electronic properties of the family of layered organic molecular crystals kappa-(BEDT-TTF)2X where X is an anion (e.g., X=I3, Cu[N(CN)2]Br, Cu(SCN)2) are reviewed. These materials are particularly interesting because of…
$\alpha$-(BEDT-TTF)$_2$I$_3$ is a prominent example of charge ordering among organic conductors. In this work we explore the details of transport within the charge-ordered as well as semimetallic phase at ambient pressure. In the…
We examine the effects of strain and cation substitution on the superconducting phase of polar semiconductors near a ferroelectric quantum phase transition with a model that combines a strong coupling theory of superconductors with a…
Polar and chiral crystal symmetries confer a variety of potentially useful functionalities upon solids by coupling otherwise noninteracting mechanical, electronic, optical, and magnetic degrees of freedom. We describe two unstudied phases…
An outstanding challenge in materials science and physics is the harnessing of light for switching charge order in e.g., ferroelectrics. Here we propose a mechanism through which electrons in ferroelectric bilayers excited with light cause…
We present a scenario for the peculiar coexistence of charge fluctuations observed in quasi-2D 1/4-filled organic conductors $\theta$-(BEDT-TTF)$_2X$ in the quantum critical regime where the charge ordering is suppressed down to zero…
Magnetoelectric properties of a coupled spin-electron model on a doubly decorated square lattice in an external electric field applied along the crystallographic axis [11] are rigorously examined with the help of generalized…
Recent advances in cold atom experimentation suggest that studies of quantum two-dimensional melting of dipolar molecules, with dipoles aligned perpendicular to ordering plane, may be on the horizon. An intriguing aspect of this problem is…
The discovery of two-dimensional (2D) materials possessing switchable spontaneous polarization with atomic thickness opens up exciting opportunities to realize ultrathin, high-density electronic devices with potential applications ranging…
The proton ordering model for the KH$_{2}$PO$_{4}$ type ferroelectrics is modified by taking into account non-linear effects, namely, the dependence of the effective dipole moments on the proton ordering parameter. Within the four-particle…
Using spectral ellipsometry, we have measured the dielectric function of a Na$_{0.82(2)}$CoO$_2$ crystal that exhibits bulk antiferromagnetism with T$_{N}$=19.8 K. We identify two prominent transitions as a function of temperature. The…
Full pattern Le-Bail refinement using x-ray powder diffraction profiles of Sr1-xCaxTiO3 for x=0.02, 0.04 in the temperature range 12 to 300 K reveals anomalies in the unit cell parameters at 170, 225 K due to an antiferrodistortive (cubic…
We investigate ferroelectric polariation as well as the formation of long-range order and the carrier density distribution in type-II Weyl semimetal WTe$_{2}$ in $T_{d}$ phase. It is been found that the metallicity and ferroelectricity can…
Multiferroics, showing simultaneous ordering of electrical and magnetic degrees of freedom, are remarkable materials as seen from both the academic and technological points of view. A prominent mechanism of multiferroicity is the…