Electromagnetically Induced Transparency (EIT) and Autler-Townes (AT) splitting in the Presence of Band-Limited White Gaussian Noise

TL;DR

This study examines how band-limited white Gaussian noise affects electromagnetically induced transparency and Autler-Townes splitting in Rydberg atom-based RF electric field measurements, highlighting noise-induced distortions and modeling their impact.

Contribution

It provides the first detailed analysis and modeling of BLWGN effects on EIT/AT signals in Rydberg atom sensors, aiding the development of noise-resilient RF measurement techniques.

Findings

EIT signals can be severely distorted by certain noise conditions.

The proposed model accurately predicts noise-induced changes in EIT signals.

Good agreement between experimental data and the model was observed.

Abstract

We investigate the effect of band-limited white Gaussian noise (BLWGN) on electromagnetically induced transparency (EIT) and Autler-Townes (AT) splitting, when performing atom-based continuous-wave (CW) radio-frequency (RF) electric (E) field strength measurements with Rydberg atoms in an atomic vapor. This EIT/AT-based E-field measurement approach is currently being investigated by several groups around the world as a means to develop a new SI traceable RF E-field measurement technique. For this to be a useful technique, it is important to understand the influence of BLWGN. We perform EIT/AT based E-field experiments with BLWGN centered on the RF transition frequency and for the BLWGN blue-shifted and red-shifted relative to the RF transition frequency. The EIT signal can be severely distorted for certain noise conditions (band-width, center-frequency, and noise power), hence altering the ability to accurately measure a CW RF E-field strength. We present a model to predict the changes in the EIT signal in the presence of noise. This model includes AC Stark shifts and on resonance transitions associated with the noise source. The results of this model are compared to the experimental data and we find very good agreement between the two.