High contrast D$_{1}$ line electromagnetically induced transparency in nanometric-thin rubidium vapor cell

TL;DR

This study demonstrates high-contrast electromagnetically induced transparency (EIT) in nanometric-thin rubidium vapor cells, enabling potential high-resolution magnetometry despite the cell's extremely small size.

Contribution

It shows that EIT can be achieved with high contrast in nanometric-thin cells, and provides a theoretical model explaining the observed phenomena.

Findings

EIT resonance with up to 40% contrast in 400-800 nm cells

EIT observed in both absorption and fluorescence spectra at low laser intensities

Potential for high-resolution magnetometry using nanometric cells

Abstract

Electromagnetically induced transparency (EIT) on atomic D$_{1}$ line of rubidium is studied using a nanometric-thin cell with atomic vapor column length in the range of L= 400 - 800 nm. It is shown that the reduction of the cell thickness by 4 orders as compared with an ordinary cm-size cell still allows to form an EIT resonance for $L= \lambda$ ($\lambda =794$ nm) with the contrast of up to 40%. Remarkable distinctions of EIT formation in nanometric-thin and ordinary cells are demonstrated. Despite the Dicke effect of strong spectral narrowing and increase of the absorption for $L=$ $\lambda /2$, EIT resonance is observed both in the absorption and the fluorescence spectra for relatively low intensity of the coupling laser. Well resolved splitting of the EIT resonance in moderate magnetic field for $L=$ $\lambda $ can be used for magnetometry with nanometric spatial resolution. The presented theoretical model well describes the observed results.