# Resolution-enhanced quantitative spectroscopy of atomic vapor in optical nanocells based on second-derivative processing of spectra

## TL;DR

This paper introduces a second-derivative spectral processing method for atomic vapor nanocells that enhances resolution and enables precise quantitative spectroscopy, including hyperfine measurements, isotope analysis, and magnetic field effects.

## Contribution

The paper presents a novel second-derivative processing technique that accurately extracts narrow spectral features from broad inhomogeneous profiles in atomic vapor nanocells.

## Key findings

- Successfully measured hyperfine splitting and transition probabilities
- Developed an atomic frequency reference with improved accuracy
- Studied atom-surface interactions and magnetic field effects

## Abstract

We present a method for recovery of narrow homogeneous spectral features out of broad inhomogeneous overlapped profile based on second-derivative processing of the absorption spectra of alkali metal atomic vapor nanocells. The method is shown to preserve the frequency positions and amplitudes of spectral transitions, thus being applicable for quantitative spectroscopy. The proposed technique was successfully applied and tested for: measurements of hyperfine splitting and atomic transition probabilities; development of an atomic frequency reference; determination of isotopic abundance; study of atom-surface interaction; and determination of magnetic field-induced modification of atomic transitions frequency and probability. The obtained experimental results are fully consistent with theoretical modeling.