Quantitative study of desctructive quantum interference effect on the linklin CPT

TL;DR

This paper explores the destructive quantum interference effects in lin||lin CPT in rubidium atoms, combining experimental and theoretical analysis to understand how various parameters influence the CPT signal.

Contribution

It provides a detailed quantitative analysis of destructive quantum interference in lin||lin CPT, including the effects of laser detuning, pressure broadening, and laser linewidth.

Findings

Quantum interference significantly affects CPT signal amplitude.

Laser linewidth impact depends on specific experimental conditions.

Optimal conditions identified where laser linewidth does not degrade CPT signal.

Abstract

We investigate experimentally and theoretically the Coherent Population Trapping (CPT) effect occurring in 87Rb D1 line due to the interaction with linearly polarized laser light (lin||lin CPT). In this configuration the coherence has a quadrupol like nature and is strongly influenced by the hyperfine structure of the excited state; consequently the quantum interference between CPT states is an essential feature of this interaction scheme. We study the lin||lin CPT signal as a function of the laser optical detuning. The comparison between experimental and theoretical results allows us to quantify the contribution from different CPT states to the total signal. Based on these results we investigate the signal depending on both the pressure broadening of the optical transition and the laser linewidth, and we find in which conditions the laser linewidth does not degrade the amplitude of the lin||lin CPT.