Related papers: Generalized Linear Response Theory for Pumped Syst…
The quantum features of ultrashort-pulse optical parametric oscillators (OPOs) are investigated theoretically in the nonlinear regime near and above threshold. Viewing the pulsed OPO as a multimode open quantum system, we rigorously derive…
We present a linear-response formalism for a system of correlated electrons out of equilibrium, as relevant for the probe optical absorption in pump-probe experiments. We consider the time dependent optical conductivity $\sigma(\omega,t)$…
A model to simulate the phenomenon of random lasing is presented. It couples Maxwell's equations with the rate equations of electronic population in a disordered system. Finite difference time domain methods are used to obtain the field…
The transient response of an intrinsic graphene, which is caused by the ultrafast interband transitions, is studied theoretically for the range of pumping correspondent to the saturated absorption regime. Spectral and temporal dependencies…
We present the first fully ab initio calculations for attosecond transient absorption spectroscopy of atomic krypton with overlapping pump and probe pulses. Within the time-dependent configuration interaction singles (TDCIS) approach, we…
We present a general formulation to calculate the dynamic optical conductivity, beyond the linear response regime, of any electronic system whose quasiparticle dispersion is described by a two band model. Our phenomenological model is based…
We present a comprehensive theoretical framework for calculating the linear and nonlinear optical responses of time-periodic quantum systems. Using density matrix evolution in the Floquet basis and adopting the length gauge, our approach…
We consider group delay and broadening using two strongly absorbing and widely spaced resonances. We derive relations which show that very large pulse bandwidths coupled with large group delays and small broadening can be achieved. Unlike…
A theory of pump-probe spectroscopy is developed in which optical fields drive two-photon Raman transitions between ground states of an ensemble of three-level $\Lambda $ atoms. Effects related to the recoil the atoms undergo as a result of…
Using Linear Response Theory, with appropriate wave functions and energies from perturbation method, the absorption profiles can be calculated for all three classes of mixed-valence systems as defined by Robin and Day : Class III…
A frequency-based omni-temporal dispersion theory is developed to capture the transient interplay between diffusion, advection, and reaction during solute transport through porous media. Unlike classical asymptotic dispersion theories,…
We report on a tunable all-optical delay line for pulses with optical frequency within the Rb $D_2$ absorption line. Using frequency tuning between absorption components from different isotopes, pulses of 10 ns duration are delayed in a 10…
The theory for time-resolved photoemission spectroscopy as applied to pump-probe experiments is developed and solved for the generic case of a strongly correlated material. The formal development incorporates all of the nonequilibrium…
The development of high-intensity ultrashort laser pulses unlocks the potential of pump-probe spectroscopy in sub-femtosecond timescale. Notably, subcycle pump pulses can generate electronic states unreachable by conventional multicycle…
The principal of linear superposition is investigated in the computational system of a solid spherical absorber immersed in a transparent aqueous medium and illuminated by a laser pulse. The absorber is exposed to a single top-hat pulse and…
The theory of nonlinear response for Markov processes obeying a master equation is formulated in terms of time-dependent perturbation theory for the Green's functions and general expressions for the response functions up to third order in…
We employ the Dynamical Projective Operatorial Approach (DPOA) to investigate the ultrafast optical excitations of germanium under intense, ultrashort pump pulses. The method has very low resource demand relative to many other available…
Optical pump-probe techniques like absorption spectroscopy and microwave conductivity are widely used to characterize the carrier dynamics in perovskites for optoelectronic applications. In contrast to the prevalent assumption of…
Optical pump-probe spectroscopy is a powerful tool for the study of non-equilibrium electronic dynamics and finds wide applications across a range of fields, from physics and chemistry to material science and biology. However, a shortcoming…
Molecular absorption and photo-electron spectra can be efficiently predicted with real-time time-dependent density-functional theory (TDDFT). We show here how these techniques can be easily extended to study time-resolved pump-probe…