Related papers: Metallic electro-optic effects in topological chir…
Using a density functional based electronic structure method, we study the effect of crystalline dielectrics on the metallic surface states of Bismuth- and chalcogen-based binary and ternary three dimensional topological insulator (TI) thin…
Pyrochlore iridates have attracted significant interest due to their complex phase behavior arising from the interplay among electron correlations, quantum metric in flat bands, geometrically frustrated lattices, and topology induced by…
We propose to use ferroelectric (Eu,Ba)TiO$_3$ ceramics just above their magnetic ordering temperature for a sensitive electron electric dipole moment search. We have synthesized a number of such ceramics with various Eu concentrations and…
Electron motion in crystals is governed by the coupling between crystal momentum and internal degrees of freedom such as spin implicit in the band structure. The description of this coupling in terms of a momentum-dependent effective field…
The second-order nonlinear Hall effect illuminates a frequency-doubling transverse current emerging in quantum materials with broken inversion symmetry even when time-reversal symmetry is preserved. This nonlinear response originates from…
Multifold fermions are generalizations of two-fold degenerate Weyl fermions with three-, four-, six- or eight-fold degeneracies protected by crystal symmetries, of which only the last type is necessarily non-chiral. Their low energy degrees…
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…
The Berry curvature dipole is well-known to cause Hall conductivity. This study expands on previous results to demonstrate how two- and three-dimensional materials react under a tilted magnetic field in the linear and nonlinear regimes. We…
The oscillatory tilt effect in a normal metal at external magnetic field is discovered. The oscillatory tilt effect is characterized by the oscillations of ultrasound attenuation in a metal at external magnetic field as predicted in [1].…
Topological defects in Bloch bands, such as Dirac points in graphene, and their resulting Berry phases play an important role for the electronic dynamics in solid state crystals. Such defects can arise in systems with a two-atomic basis due…
Material anisotropy and chirality produce polarization-dependent light-matter interactions. Absorption leads to linear and circular dichroism, whereas elastic forward scattering produces linear and circular birefringence. Here we highlight…
The nonlinear Hall effect (NLHE), an emergent response in systems with broken inversion symmetry, provides a powerful tool for probing topological transport properties. In this context, we investigate copper-substituted lead apatite…
Recently it has been discovered that in Weyl semimetals the surface state Berry curvature can diverge in certain regions of momentum. This occurs in a continuum description of tilted Weyl cones, which for a slab geometry results in the…
A valley-contrasting Berry curvature in bilayer transition metal dichalcogenides with spin-orbit coupling can generate valley magnetization when the inversion symmetry is broken, for example, by an electric field, regardless of…
The current density ${\bf j}^{\rm{\bf B}}$ induced in a clean metal by a slowly-varying magnetic field ${\bf B}$ is formulated as the low-frequency limit of natural optical activity, or natural gyrotropy. Working with a multiband Pauli…
The quantum behaviour of electrons in materials lays the foundation for modern electronic and information technology. Quantum materials with novel electronic and optical properties have been proposed as the next frontier, but much remains…
Within the wave-packet semiclassical approach, the Bloch electron energy is derived to second order in the magnetic field and classified into gauge-invariant terms with clear physical meaning, yielding a fresh understanding of the complex…
Chirality manifests across multiple scales, yielding unique phenomena that break mirror symmetry. In chiral materials, unexpectedly large spin-filtering or photogalvanic effects have been observed even in materials composed of light…
Recent experiments have demonstrated interesting physics in a family of two-dimensional (2D) composition-tunable materials Nb$_{2n+1}$Si$_n$Te$_{4n+2}$. Here, we show that owing to its intrinsic low symmetry, metallic nature, tunable…
We propose a novel means to isolate and quantify the effects of Berry force on molecular dynamics using two reasonably strong continuous wave (CW) laser fields with frequencies $\omega$ and $2\omega$. For molecules or materials with three…