Creation of Coherent Superposition States in Inhomogeneously Broadened Media with Relaxation

TL;DR

This paper presents a robust scheme for creating coherent superposition states in inhomogeneously broadened media using frequency-chirped laser pulses, with minimal atomic excitation and resilience to parameter variations.

Contribution

It introduces a novel method for on-demand superposition state creation in inhomogeneously broadened media with detailed analysis of relaxation effects.

Findings

The scheme is robust against parameter variations.

Efficient in both homogeneously and Doppler-broadened media.

Minimal atomic excitation during superposition creation.

Abstract

We propose and analyze a scheme for "on demand" creation of coherent superposition of meta-stable states in a tripod-structured atom using frequency-chirped laser pulses. Negligible excitation of the atoms during the creation of the superposition states is a priority in our consideration. The underlying physics of the scheme is explained using the formalism of adiabatic states. By numerically solving master equation for the density matrix operator, we analyze the influence of the spontaneous decay and transverse relaxation on the efficiency of the creation of superposition states. We show that the proposed scheme is robust against small-to-medium variations of the parameters of the laser pulses. We provide a detailed analysis of the effect of the inhomogeneous (Doppler-) broadening on the efficiency of the coherence creation and show that the proposed scheme may be equally efficient in both homogeneously and Doppler-broadened media.