Probing Macroscopic Quantum Superpositions with Nanorotors

TL;DR

This paper proposes a novel experimental method to test macroscopic quantum superpositions using nanorotors, enabling studies at the quantum-classical boundary with practical advantages over existing techniques.

Contribution

It introduces a new approach to observe quantum superpositions in nanoscale rotors without diffraction gratings, facilitating experiments with massive objects under realistic conditions.

Findings

Demonstrates orientational quantum revivals in nanorotors

Proposes a feasible experimental setup for macroscopic superpositions

Highlights potential applications in quantum sensors and fundamental tests

Abstract

Whether quantum physics is universally valid is an open question with far-reaching implications. Intense research is therefore invested into testing the quantum superposition principle with ever heavier and more complex objects. Here we propose a radically new, experimentally viable route towards studies at the quantum-to-classical borderline by probing the orientational quantum revivals of a nanoscale rigid rotor. The proposed interference experiment testifies a macroscopic superposition of all possible orientations. It requires no diffraction grating, uses only a single levitated particle, and works with moderate motional temperatures under realistic environmental conditions. The first exploitation of quantum rotations of a massive object opens the door to new tests of quantum physics with submicron particles and to quantum gyroscopic torque sensors, holding the potential to improve state-of-the art devices by many orders of magnitude.