Cooling a Micromechanical Beam by Coupling it to a Transmission Line

TL;DR

This paper proposes a method to cool a micromechanical beam by coupling it to a superconducting transmission line, using microwave driving to induce a Coulomb force that opposes the beam's motion, potentially enabling quantum ground state preparation.

Contribution

It introduces a novel cooling mechanism for micromechanical beams via capacitive coupling to a transmission line driven by microwaves, feasible with current technology.

Findings

Coulomb force can oppose beam velocity to achieve cooling

Cooling mechanism is effective when microwave frequency is below transmission line resonance

Method is feasible under current experimental conditions

Abstract

We study a method to cool down the vibration mode of a micro-mechanical beam using a capacitively-coupled superconducting transmission line. The Coulomb force between the transmission line and the beam is determined by the driving microwave on the transmission line and the displacement of the beam. When the frequency of the driving microwave is smaller than that of the transmission line resonator, the Coulomb force can oppose the velocity of the beam. Thus, the beam can be cooled. This mechanism, which may enable to prepare the beam in its quantum ground state of vibration, is feasible under current experimental conditions.