Related papers: Light-induced electronic polarization in antiferro…
Antiferromagnetism (AF) in AB'-stacked centrosymmetric bilayer (BL) CrI$_3$ breaks both spatial inversion ($P$) and time-reversal ($T$) symmetries but maintains the combined $PT$ symmetry, thus inducing novel second-order nonlinear optical…
Analysis of the electronic state of the CuO2 planes of high-Tc materials has been performed with special regard to the influence of the Coulomb interactions separated after moments. Different symmetry breaking effects were revealed. A…
We develop a comprehensive theory for magnetoelectricity in magnetically ordered quasi-2D systems whereby in thermal equilibrium an electric field can induce a magnetization $m$ and a magnetic field can induce a polarization. This effect…
Ba2CoGe2O7, crystallizing in the noncentrosymmetric but nonpolar structure, belongs to a special class of multiferroic materials, whose properties are predetermined by the rotoinversion symmetry. Unlike inversion, the rotoinversion symmetry…
We propose a way to use electric-field to control the magnetic ordering of the tetragonal BiFeO3. Based on systematic first-principles studies of the epitaxial strain effect on the ferroelectric and magnetic properties of the tetragonal…
Large electron-electron Coulomb-interactions in correlated systems can lead to a periodic arrangement of localized electrons, the so called "charge-order". The latter is here proposed as a driving force behind ferroelectricity in iron…
Symmetry engineering is explicitly effective to manipulate and even create phases and orderings in strongly correlated materials. Flexural stress is universally practical to break the space-inversion or time-reversal symmetry. Here, by…
Bulk LiOsO3 was experimentally identified as a "ferroelectric" metal where polar distortions coexist with metallicity [Shi et al., Nature Materials 12, 1024 (2013)]. It is generally believed that polar displacements in a "ferroelectric"…
We present a microscopic theory for ultrafast control of solids with high-intensity terahertz frequency optical pulses. When resonant with selected infrared-active vibrations, these pulses transiently modify the crystal structure and lead…
While the understanding of altermagnetism is still at a very early stage, it is expected to play a role in various fields of condensed matter research, for example spintronics, caloritronics and superconductivity. In the field of optical…
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…
We study electric polarization and nonlinear optical effects in spin systems with broken inversion symmetry. We apply strong coupling expansion to the underlying electronic Hamiltonians, and systematically derive expressions for electric…
Antiferroelectric liquid crystals can be considered as a promising alternative to nematic mixtures in the area of microdisplays. Switching behaviour of the molecules has been modelled as two adjacent smectic layers. However, some studies…
Symmetry is a basic paradigm for analysis of problems in solid state physics, and to controllably break point-group symmetries is a powerful probe of novel forms of order. In this work, we apply two methods, controlled lattice strain and…
We analyze the polar Kerr effect in an itinerant electron system on a square lattice in the presence of a composite charge order proposed for the pseudogap state in underdoped cuprates. This composite charge order preserves discrete…
There is growing interest in the photo-induced generation of rectified current, namely photocurrent phenomenon. While the response was attributed to noncentrosymmetric structures of crystals, the parity violation accompanied by the magnetic…
We show that time-reversal symmetry broken, centrosymmetric antiferromagnets with nonrelativistic spin-splitting are conveniently described in terms of the ferroic ordering of magnetic octupoles. The magnetic octupoles are the lowest-order…
A previous work, ref. 2 experimentally confirmed that measured special polarization characteristic features of a three-dimensional terahertz (THz) photonic-crystal did not apparently apply to general physical- and optical- basic rules. It…
Recent studies have drawn growing attention on non-relativistic odd-parity magnetism in the wake of altermagnets. Nevertheless, odd-parity spin splitting is often believed to appear in non-collinear magnetic configurations. Here, using…
We report the observation of the electro-optic effect in Bi$_2$Se$_3$ crystals induced by an intense single-cycle terahertz pulse. The effect reveals itself as a transient change of the polarization state of a femtosecond laser pulse…