Strong magnetic coupling between an electronic spin qubit and a mechanical resonator

TL;DR

This paper presents a method for achieving strong, coherent coupling between a single electronic spin qubit in diamond and a nano-mechanical resonator, enabling quantum control and measurement of the resonator's state.

Contribution

The authors demonstrate a technique to couple a spin qubit with a mechanical resonator using dressed spin states, allowing for ground state cooling and quantum superposition generation.

Findings

Strong spin-resonator coupling achieved

Ground state cooling of the resonator demonstrated

Quantum superpositions of resonator states generated

Abstract

We describe a technique that enables a strong, coherent coupling between a single electronic spin qubit associated with a nitrogen-vacancy impurity in diamond and the quantized motion of a magnetized nano-mechanical resonator tip. This coupling is achieved via careful preparation of dressed spin states which are highly sensitive to the motion of the resonator but insensitive to perturbations from the nuclear spin bath. In combination with optical pumping techniques, the coherent exchange between spin and motional excitations enables ground state cooling and the controlled generation of arbitrary quantum superpositions of resonator states. Optical spin readout techniques provide a general measurement toolbox for the resonator with quantum limited precision.