Experimental Realization of Rabi-Driven Reset for Fast Cooling of a High-Q Cavity

TL;DR

This paper introduces a measurement-free, fast cavity reset method using Rabi-driven cooling, significantly improving reset speed and efficiency for quantum memories in superconducting circuits.

Contribution

The authors demonstrate a novel Rabi-Driven Reset technique that enables rapid, measurement-free cooling of a superconducting cavity, overcoming limitations of previous methods.

Findings

Achieved cavity reset with decay time of 1.2 microseconds.

Reset approximately 30 thermal photons in 80 microseconds.

Demonstrated over two orders of magnitude faster reset than intrinsic lifetime.

Abstract

High-Q bosonic memories are central to hardware-efficient quantum error correction, but their isolation makes fast, high-fidelity reset a persistent bottleneck. Existing approaches either rely on weak intermode cross-Kerr conversion or on measurement-based sequences with substantial latency. Here we demonstrate a hardware-efficient Rabi-Driven Reset (RDR) that implements continuous, measurement-free cooling of a superconducting cavity mode. A strong resonant Rabi drive on a transmon, together with sideband drives on the memory and readout modes detuned by the Rabi frequency, converts the dispersive interaction into an effective Jaynes-Cummings coupling between the qubit dressed states and each mode. This realizes a tunable dissipation channel from the memory to the cold readout bath. Crucially, the engineered coupling scales with the qubit-mode dispersive interaction and the drive amplitude, rather than with the intermode cross-Kerr, enabling fast cooling even in very weakly coupled architectures that deliberately suppress direct mode-mode coupling. We demonstrate RDR of a single photon with a decay time of $1.2 \mu s$, more than two orders of magnitude faster than the intrinsic lifetime. Furthermore, we reset about 30 thermal photons in about $80 \mu s$ to a steady-state average photon number of $\bar{n} = 0.045 \pm 0.025$.