Quantum Magnetomechanics with Levitating Superconducting Microspheres

TL;DR

This paper proposes a method to achieve ground-state cooling and quantum superpositions of a levitating superconducting microsphere's center-of-mass motion by combining magnetic trapping and superconducting qubits, leveraging low environmental coupling.

Contribution

It introduces a novel approach to quantum magnetomechanics using levitating superconducting microspheres, enabling quantum control of relatively large objects.

Findings

Mechanical motion is well isolated from environment due to absence of clamping losses.

Feasibility of ground-state cooling of microspheres demonstrated.

Potential for quantum superposition states of macroscopic objects.

Abstract

We show that by magnetically trapping a superconducting microsphere close to a quantum circuit, it is experimentally feasible to perform ground-state cooling and to prepare quantum superpositions of the center-of-mass motion of the microsphere. Due to the absence of clamping losses and time dependent electromagnetic fields, the mechanical motion of micrometer-sized metallic spheres in the Meissner state is predicted to be very well isolated from the environment. Hence, we propose to combine the technology of magnetic microtraps and superconducting qubits to bring relatively large objects to the quantum regime.