Fluorescence of rubidium vapor in a transient interaction regime

TL;DR

This study investigates how the fluorescence spectra of room-temperature rubidium vapor change when the laser frequency is scanned rapidly, revealing a transition from steady-state to transient interaction regimes and enabling atomic parameter determination.

Contribution

It introduces a theoretical and experimental analysis of transient effects in rubidium vapor fluorescence under rapid laser frequency scanning, a novel approach for atomic parameter measurement.

Findings

Spectral modifications depend on scan speed, especially above 10^6 MHz/s.

Transient effects cause asymmetry in rising and falling slopes of spectra.

Results align with the developed theoretical model.

Abstract

We have studied modification of the fluorescence spectra of a room-temperature atomic rubidium vapor in the region of $^{85}$Rb and $^{87}$Rb D$_2$ line while changing the temporal rate of linear (triangular) scanning of laser radiation frequency. Increase of the ramping speed over certain value ($\approx$ 10$^6$ MHz/s) results in essential modification of magnitudes of individual atomic transitions, different on rising and falling slopes, which characterize transition from a steady-state interaction regime to a transient one. Our experimental results are well consistent with the developed theoretical model. The obtained results can be used for determination of atomic system parameters such as ground-state relaxation rate. Possible follow-up actions on addressed control of atomic levels population is discussed.