Related papers: Intrinsic Fermi Surface Contribution to the Bulk P…
Quantum materials governed by emergent topological fermions have become a cornerstone of physics. Dirac fermions in graphene form the basis for moir\'e quantum matter, and Dirac fermions in magnetic topological insulators enabled the…
In periodic media, despite the close relationship between geometrical effects in the bulk and topological surface states, the two are typically probed separately. We show that when beams in a Weyl medium reflect off an interface with a…
Coupling different physical properties is a fascinating subject of physics. Already well-known are the multiferroics which show properties of ferroelectrics and magnets. But ferroelectricity by itself also entails the bulk photovoltaic…
Weyl semimetals constitute a newly discovered class of three-dimensional topological materials with linear touchings of valence and conduction bands in the bulk. The most striking property of topological origin in these materials, so far…
Photovoltaic Hall effect, i.e., generation of a photocurrent perpendicular to the bias electric field, is an interesting platform of Berry curvature engineering by external fields. Floquet engineering aims at generation of light-induced…
The chiral photocurrent or circular photogalvanic effect (CPGE) is a photocurrent that depends on the sense of circular polarization. In a disorder-free, noninteracting chiral Weyl semimetal, the magnitude of the effect is approximately…
The two-dimensional (2D) bulk photovoltaic effect (BPVE) is a cornerstone for future highly efficient 2D solar cells and optoelectronics. The ferromagnetic semiconductor 2H-FeCl2 is shown to realize a new type of BPVE in which spatial…
Using Green's function of semi-infinite Weyl semimetals we find that the collective charge excitations of Fermi arcs in undoped Weyl semi-metals are linearly dispersing gapless plasmon modes. The gaplessness comes from proper consideration…
A simple effective model for the intermediate-density regime is constructed from the high-density effective theory of quantum chromodynamics (QCD). In the effective model, under a renormalization-group (RG) scaling towards low momenta, the…
We report the detection of zero-bias photocurrents induced by interband excitation using oblique near-infrared light ({\lambda}=0.780 {\mu}m) along the directions parallel and perpendicular to the helical axis in a millimeter-sized Te…
Materials that rectify light into current in their bulk are desired for optoelectronic applications. In inversion-breaking Weyl semimetals, bulk photocurrents may arise due to nonlinear optical processes that are enhanced near the Weyl…
We present results of a theoretical study of photocurrents in the Weyl semimetals belonging to the gyrotropic symmetry classes. We show that, in weakly gyrotropic symmetry classes C$_{nv}$ ($n = 3,4,6$), the circular photocurrent transverse…
The bulk photovoltaic effect (BPVE) refers to the direct current generation in a noncentrosymmetric material under illumination and can be applied to solar energy technology. BPVE includes injection and shift currents, led by the change of…
Domain walls in three-dimensional Weyl semimetals, formed by localized magnetic moments, are investigated. There appear bound states around the domain wall with the discrete spectrum, among which we find "Fermi arc" states with the linear…
The bulk photovoltaic effect (BPVE) generates a direct current photocurrent under uniform irradiation and is a nonlinear optical effect traditionally studied in non-centrosymmetric materials. The two main origins of BPVE are the shift and…
The response to an electric field (DC and AC) of electronic systems in which the Fermi "surface" consists of a number of 3D Weyl points (such as some pyrochlore iridates) exhibits a peculiar combination of characteristics usually associated…
Utilizing spin or valley degree of freedom is one of the promising approaches to realize more energy-efficient information processing. In the 2D transition metal dichalcogenide, the spin/valley current can be generated by utilizing the…
Nonlinear optical responses of quantum materials have recently undergone dramatic developments to unveil nontrivial geometry and topology. A remarkable example is the quantized longitudinal circular photogalvanic effect (CPGE) associated…
Floquet engineering, the concept of tailoring a system by a periodic drive, is increasingly exploited to design and manipulate topological phases of matter. In this work, we study periodically driven higher-order topological Dirac…
Non-Hermitian physics, studying systems described by non-Hermitian Hamiltonians, reveals unique phenomena not present in Hermitian systems. Unlike Hermitian systems, non-Hermitian systems have complex eigenvalues, making their effects less…