Evidence for strong van der Waals-type Rydberg-Rydberg interaction in thermal vapor

TL;DR

This paper provides experimental evidence of strong van der Waals-type Rydberg-Rydberg interactions in a thermal vapor, demonstrating potential for thermal quantum devices operating at GHz frequencies.

Contribution

It is the first to observe Rydberg interactions in a hot vapor, showing they can surpass Doppler broadening and enabling thermal quantum technology applications.

Findings

Rabi oscillations observed in a vapor cell experiment

Interaction strength scales with Rydberg quantum number n

Interaction exceeds Doppler width in the thermal vapor

Abstract

We present evidence for Rydberg-Rydberg interaction in a gas of rubidium atoms above room temperature. Rabi oscillations on the nanosecond timescale to different Rydberg states are investigated in a vapor cell experiment. Analyzing the atomic time evolution and comparing to a dephasing model we find a scaling with the Rydberg quantum number n that is consistent with van der Waals interaction. Our results show that the interaction strength can be larger than the kinetic energy scale (Doppler width) which is the requirement for realization of thermal quantum devices in the GHz regime.