Accurate density measurement of a cold Rydberg gas via non collisional two-body transitions

TL;DR

This paper presents a novel, highly accurate method for measuring the density of a frozen Rydberg gas using adiabatic two-body dipole-dipole transitions induced by electric field sweeps, which does not require prior volume or detection efficiency knowledge.

Contribution

The authors introduce an original, non-collisional technique based on adiabatic two-body transitions for precise Rydberg gas density measurement, independent of volume or detection efficiency assumptions.

Findings

Method achieves high accuracy in density measurement

Efficiency of two-body process depends strongly on gas density

Calibration of Rydberg detection without prior volume estimation

Abstract

We experimentally demonstrate an original method to measure very accurately the density of a frozen Rydberg gas. It is based on the use of adiabatic transitions induced by the long-range dipole-dipole interaction in pairs of nearest neighbor Rydberg atoms by sweeping an electric field with time. The efficiency of this two-body process is experimentally tunable, depends strongly on the density of the gas and can be accurately calculated. The analysis of this efficiency leads to an accurate determination of the Rydberg gas density, and to a calibration of the Rydberg detection. Our method does not require any prior knowledge or estimation of the volume occupied by the Rydberg gas, or of the efficiency of the detection.