Torque-free manipulation of nanoparticle rotations via embedded spins

TL;DR

This paper demonstrates that embedded spins in symmetric nanorotors can be used to control their rotations without external torque, enabling quantum-level manipulation of nanoparticle spins and rotations.

Contribution

It introduces a novel torque-free method to manipulate nanoparticle rotations using intrinsic spins, expanding quantum control techniques.

Findings

Embedded spins significantly influence nanorotor dynamics.

Observable effects in freely rotating nanodiamonds with NV centers.

Potential for quantum-level rotation control without external torque.

Abstract

Spin angular momentum and mechanical rotation both contribute to the total angular momentum of rigid bodies, leading to spin-rotational coupling via the Einstein-de Haas and Barnett effects. Here we show that the revolutions of symmetric nanorotors can be strongly affected by a small number of intrinsic spins. The resulting dynamics are observable with freely rotating nanodiamonds with embedded nitrogen-vacancy centers and persist for realistically-shaped near-symmetric particles, opening the door to torque-free schemes to control their rotations at the quantum level.