Cooling a micro-mechanical resonator by quantum back-action from a noisy qubit

TL;DR

This paper investigates how qubit dephasing affects the ability to cool a mechanical resonator to its ground state using quantum back-action, emphasizing the importance of low dephasing rates.

Contribution

It demonstrates that effective ground-state cooling requires the qubit dephasing rate to be sufficiently low, highlighting the critical role of qubit coherence in quantum cooling.

Findings

Ground-state cooling depends on low qubit dephasing.

Superconducting flux qubit can cool a resonator via quantum back-action.

High dephasing rates hinder effective cooling.

Abstract

We study the role of qubit dephasing in cooling a mechanical resonator by quantum back-action. With a superconducting flux qubit as a specific example, we show that ground-state cooling of a mechanical resonator can only be realized if the qubit dephasing rate is sufficiently low.