A broad-band laser-driven double Fano system—photoelectron spectra

Abstract

Fano profiles, which with their asymmetric character, have many potential applications in technology. The design of Fano profiles into optical systems may create new non-linear and switchable metamaterials, high-quality optical waveguides, ultrasensitive media for chemical or biosensing etc. In this paper, we consider an external field driven double Fano model, in which, instead of one autoionizing state, there are two discrete states embedded in one continuum. We assume further that the external electromagnetic field can be decomposed into two parts: a deterministic (or coherent) part and a randomly fluctuating chaotic component, which is a δ-correlated, Gaussian, Markov and stationary process (white noise). This assumption corresponds to the case of the real multimode laser operating without any correlation between the modes. We solve a set of coupled stochastic integro-differential equations involving the Fano model with two discrete levels. We derive an exact formula by determining the photoelectron spectrum and compare it with the results obtained earlier in our previous papers.

A stochastic model of the influence of buffer gas collisions on Mollow spectra

“…Starting from a set of optical Bloch equations derived from nonrelativistic quantum electrodynamics in the rotating wave approximation (RWA), and shifting the atom energy by the RTS x(t) according to the idea described in Introduction, we can perform an averaging procedure over this RTS and obtain the following formula for the spectrum of RF in the presence of the collisions with the molecules of the buffer gas (since the volume of this communication is limited, we shall concentrate here only on physical aspects of the problem, whereas the mathematical details of this procedure will be presented elsewhere [15]):…”

Electromagnetically induced transparency for a double Fano-profile system

“…This generalizes the model discussed in reference [50] that contains two AI levels of the same energy. As it has been emphasized in references [51][52][53], the presence of an arbitrary additional AI state results in new quantum interference phenomena occurring in long-time photoelectron spectra which are considered in a more realistic model, where the external electromagnetic field has the white noise component [54]. Among others, it can induce an additional EIT window which parameters are controlled by the transition to (from) AI states.…”

Kerr nonlinear coupler and entanglement induced by broadband laser light

“…Hence, it is worthwhile to start with an extreme case of white noise. Even in this case we can obtain several interesting results [7][8][9]. Here we extend the formalism given in [10] to a more realistic case, when the laser width is taken into account and discuss a simple quantum information application of Kerr nonlinearities, namely for generation of entangled optical qubits from classical light.…”

“…Moreover, we also suppose that for the time t=0 both oscillators are in the states of vacuum. Thus, we derive a system of equations for stochastic averages of variables and its solutions for the probability amplitudes c ij (i,j = 0,1) in the form: (the volume of this communication is limited, so we shall concentrate here only on physical aspects of the problem, whereas the mathematical details of this procedure will be described elsewhere [11] …”