相关论文: Semiconductor-Bloch Formalism: Derivation and Appl…
We present studies of high-order harmonic generation (HHG) at laser intensities well above saturation. We use driving laser pulses which present a particular electron dynamics in the turn-on stage. Our results predict an increasing on the…
We study high-order harmonic generation by optically driven one- and two-dimensional hydrogenlike atoms formed by Coulomb imurities in graphene. The time-dependent Dirac equations with Coulomb plus time-periodic monochromatic field…
Electric conductivities may reveal the topological and magnetic properties of band structures in solids, especially for two-dimensional unpaired Dirac fermions. In this work, we evaluate the longitudinal and Hall conductivity for unpaired…
Topological materials are of interest to both fundamental science and advanced technologies, because topological states are robust with respect to perturbations and dissipation. Experimental detection of topological invariants is thus in…
A new pairing theory for many-fermion systems is obtained via the Dirac supersymmetry framework recently introduced to describe Dirac particles in external potentials. It is shown that the standard Bogoliubov-Valatin canonical…
We employ a rotating frame of reference to elucidate high-harmonic generation of circularly polarized light by bicircular driving fields. In particular, we show how the experimentally observed circular components of the high-harmonic…
We obtain a class of adiabatic solutions of Dirac equation for the charged massless relativistic quasi-particles that arise from the low-energy excitations \cite{foot-1} in a 2D graphene sheet, interacting with an electromagnetic field. The…
The Berry phase and curvature are studied for the Dirac nodal line semimetal of single-component molecular conductor [Pd(dddt)$_2$]. Using two-band model on the basis of a tight-binding model, it is shown that the Berry curvature,…
A theoretical model for high-order harmonic generation (HHG) in bulk solids is considered. Our approach treats laser-induced inter- and intraband currents on an equal footing. The sum of these currents is the source of the high-order…
We present a method for constructing a consistent low energy canonical formalism for higher order time-derivative theories, extending the Dirac method to include perturbative Hamiltonian constraints. We apply it to two paradigmatic…
Recent studies have demonstrated that the polarization states of high harmonics from solids can differ from those of the driving pulses. To gain insights on the microscopic origin of this behavior, we perform one-particle intraband-only…
This Letter brings together two topics that, until now, have been the focus of intense but non-overlapping research efforts. The first concerns high harmonic generation in solids, which occurs when intense light field excites highly…
Engineered micro- or nano-structures based on nonlinear optical materials offer versatile opportunities for optoelectronic applications. While extensive efforts have been devoted to design tailored microcavities to promote and increase the…
We present calculation of photoexcitation and high-harmonic generation in bulk diamond induced by intense near-infrared laser pulse of photon energy 1.55 eV, time duration of 15 fs and peak field strength $F=$ 0.4 V/{\AA}. Depending on the…
This paper presents a theory of interaction-induced band-flattening in strongly correlated electron systems. We begin by illustrating an inherent connection between flat bands and index theorems, and presenting a generic prescription for…
This talk presents a study of massless relativistic Dirac fields in three Euclidean dimensions, at finite temperature and density, in the presence of a uniform electromagnetic background. Apart from explaining the behavior of Hall's…
It is shown that virtually all nonlinear and/or time-varying loads that generate harmonic current distortion can be characterized in terms of so-called higher-order circuit elements. The most relevant higher-order elements exploited in this…
Heavily doped semiconductors have emerged as tunable low-loss plasmonic materials at mid-infrared frequencies. In this article we investigate nonlinear optical phenomena associated with high concentration of free electrons. We use a…
Topological node of electronic bands can carry emergent charge degree of freedom such as the Berry curvature monopole of the Weyl semimetals, which results in intriguing transport and optical phenomena. In this study, we discuss the…
We propose a new band engineering scheme on the biphenylene network, a newly synthesized carbon allotrope. First, we investigate the mechanism for the appearance of type II Dirac fermion in a pristine biphenylene network. We show that the…