Microwave saturation of the Rydberg states of electrons on helium

TL;DR

This study investigates microwave excitation of Rydberg states in electrons on helium, demonstrating saturation effects, power broadening, and the potential for qubit applications due to favorable Rabi frequency to linewidth ratios.

Contribution

It provides experimental measurements of microwave saturation and power broadening in Rydberg states of electrons on helium, highlighting their suitability for quantum computing.

Findings

Linewidth agrees with theoretical predictions and is very small below 300 mK.

Absorption saturation observed at high excitation fractions.

High Rabi frequency to linewidth ratio indicates potential for qubit development.

Abstract

We present measurements of the resonant microwave excitation of the Rydberg energy levels of surface state electrons on superfluid helium. The temperature dependent linewidth agrees well with theoretical predictions and is very small below 300 mK. Absorption saturation and power broadening were observed as the fraction of electrons in the first excited state was increased to 0.49, close to the thermal excitation limit of 0.5. The Rabi frequency was determined as a function of microwave power. The high values of the ratio of the Rabi frequency to linewidth confirm this system as an excellent candidate for creating qubits.