Observation of interference effects via four photon excitation of highly excited Rydberg states in thermal cesium vapor

TL;DR

This paper demonstrates the observation of interference effects like EIT and EIA in highly excited Rydberg states of thermal cesium vapor using a novel four-step excitation scheme that requires less laser power and enables new applications.

Contribution

It introduces a four-step excitation scheme for Rydberg states in thermal vapor, reducing laser power requirements and enabling dephasing-free Rydberg excitation.

Findings

Observation of EIT and EIA in Rydberg states

Good agreement between experimental lineshapes and simulations

Efficient excitation scheme with lower laser power

Abstract

We report on the observation of electromagnetically induced transparency (EIT) and absorption (EIA) of highly excited Rydberg states in thermal Cs vapor using a four-step excitation scheme. The advantage of this four-step scheme is that the final transition to the Rydberg state has a large dipole moment and one can achieve similar Rabi frequencies to two- or three-step excitation schemes using two orders of magnitude less laser power. This scheme enables new applications such as dephasing free Rydberg excitation. The observed lineshapes are in good agreement with simulations based on multilevel optical Bloch equations.