Rapid laser-free ion cooling by controlled collision

TL;DR

This paper introduces a laser-free, rapid ion cooling method using controlled collisions and phonon swapping, enabling fast re-cooling of ion qubits during quantum computing without laser cooling limitations.

Contribution

It presents a novel collision-based cooling technique that swaps motional states between ions, avoiding traditional laser cooling constraints.

Findings

Method achieves rapid cooling within a few trap oscillations.

Requires only trap potential control, not laser systems.

Enables efficient re-cooling during quantum operations.

Abstract

I propose a method to remove the axial motional excitation from an ion qubit within a few oscillation periods of a harmonic trap. The principle is to prepare another coolant ion in its motional ground state, and then apply a phonon beam splitter to swap the motional state between the ions without affecting the internal state. This method requires only the precise control of the trapping potential, thus its performance does not suffer from the limitations of current laser-cooling schemes. With sufficient coolant ions pre-prepared, this method can rapidly re-cool ion qubits during quantum information processing.