Fast electromagnetic response of a thin film of resonant atoms with permanent dipole

TL;DR

This paper models the propagation of ultrashort pulses through a thin resonant atomic film with permanent dipoles, deriving solutions for reflection and transmission to help experimentally determine atomic parameters.

Contribution

It introduces a simplified wave equation approach for thin films with permanent dipole atoms and computes stationary solutions and optical coefficients.

Findings

Derived reflection and transmission coefficients for the film.

Provided a method to extract atomic parameters from optical measurements.

Validated the model with stationary solutions.

Abstract

We consider the propagation of extremely short pulses through a dielectric thin film containing resonant atoms (two level atoms) with permanent dipole. Assuming that the film width is less than the field wave length, we can solve the wave equation and reduce the problem to a system of generalized Bloch equations describing the resonant atoms. We compute the stationary solutions for a constant irradiation of the film. Superimposing a small amplitude linear wave we compute the reflection and transmission coefficients. From these, one can then deduce the different parameters of the model. We believe this technique could be used in experiments to obtain the medium atomic and relaxation parameters.