相关论文: Nonlinear optical absorption and photocurrents in …
Theory of light absorption and circular photocurrent in Weyl semimetals is developed for arbitrary large light intensities with account for both elastic and inelastic relaxation processes of Weyl fermions. The direct optical transition rate…
We discuss optical absorption in topological insulators and study possible photoelectric effects theoretically. We found that absorption of circularly polarized electromagnetic waves in two-dimensional topological insulators results in…
We report the optical absorption characteristics and the photocurrent spectra for large-area molecular junctions containing different molecular structures and thicknesses. Through experimental assessment of the optical absorption of…
We perform linear and non-linear photon absorption calculations in topological insulator ultra-thin films on a substrate. Due to the unique band structure of the coupled topological surface states, novel features are observed for suitable…
Theory of the Linear photogalvanic effect is developed for direct optical transitions between surface states of three-dimensional topological insulators. The photocurrent governed by the orientation of the polarization plane of light and…
We report on the observation of complex nonlinear intensity dependence of the circular and linear photogalvanic currents induced by infrared radiation in compensated (Bi$_{0.3}$Sb$_{0.7}$)$_2$(Te$_{0.1}$Se$_{0.9}$)$_3$ 3D topological…
A fundamental issue that limits the efficiency of many photoelectrochemical systems is that the photon absorption length is typically much longer than the electron diffusion length. Various photon management schemes have been developed to…
The light absorption due to the transitions between the edge and two-dimensional (2D) states of a 2D topological insulator (TI) is considered in the Volkov-Pankratov model. It is shown that the transitions are allowed only for the in-plane…
We report on the observation of terahertz radiation induced edge photogalvanic currents in graphene, which are nonlinear in intensity. The increase of the radiation intensities up to MW/cm$^2$ results in a complex nonlinear intensity…
Light forces induced by scattering and absorption in elastic dielectrics lead to local density modulations and deformations. These perturbations in turn modify light propagation in the medium and generate an intricate nonlinear response. We…
Topological insulators have surface states with a remarkable helical spin structure, with promising prospects for applications in spintronics. Strategies for generating spin polarized currents, such as the use of magnetic contacts and…
The polarization dependence of the low field microwave photoconductivity and absorption of a two-dimensional electron system has been investigated in a quasi-optical setup in which linear and any circular polarization can be produced…
In the last years, Infrared Reflection-Absorption Spectroscopy (IRRAS) became a standard technique to study vibrational excitations of molecules. These investigations are strongly motivated by perspective applications in monitoring chemical…
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…
Optical injection and detection of charge currents can complement conventional transport and photoemission measurements without the necessity of invasive contact that may disturb the system being examined. This is a particular concern for…
The influence of the defect position on absorption and emission in the cholesteric liquid crystal with an isotropic defect inside is studied. It is shown that for non-diffracting circularly polarized incident light absorption/emission is…
The photonic density of states (PDS) of the eigen polarizations (EPs) in cholesteric liquid crystal (CLC) cells are calculated. The exact analytic expressions for the reflection and transmission matrices for the finite thickness CLC layer…
We study the photocurrent response of topological insulator surface states to circularly polarized light for arbitrary oblique incidence. We describe the surface states within a Dirac model, including several perturbations such as hexagonal…
Topological insulators are a new phase of matter that exhibits exotic surface electronic properties. Determining the spin texture of this class of material is of paramount importance for both fundamental understanding of its topological…
We investigate the non-linear response and energy absorption in bulk silicon irradiated by intense 12-fs near-infrared laser pulses. Depending on the laser intensity, we distinguish two regimes of non-linear absorption of the laser energy:…