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

TL;DR

This paper models a double Fano system driven by a broad-band laser, deriving an exact photoelectron spectrum formula for a complex quantum interference system with noise considerations.

Contribution

It introduces a stochastic double Fano model with two discrete states in a continuum and derives an exact photoelectron spectrum formula considering laser noise effects.

Findings

Derived an exact formula for the photoelectron spectrum.

Analyzed the effects of laser noise on Fano interference.

Compared results with previous models and findings.

Abstract

Fano profiles, with their asymmetric character, have many potential applications in technology. The design of Fano profiles into optical systems may create new nonlinear 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 \delta-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 in our previous papers.