Towards a test of quantum gravity with a levitated nanodiamond containing a spin

TL;DR

This paper reviews methods for fabricating nanodiamonds with NV centers and discusses their potential use in experiments testing macroscopic quantum effects and quantum gravity.

Contribution

It provides a comprehensive overview of fabrication techniques and the spin physics of NV centers relevant to macroscopic quantum experiments.

Findings

Methods for fabricating suitable nanodiamonds are summarized.

Potential experimental setups for testing quantum gravity are discussed.

The role of NV center spin physics in these tests is analyzed.

Abstract

There is significant interest in potential experimental tests of macroscopic quantum effects, both to test potential modifications to quantum theory and to probe the quantum nature of gravity. A proposed platform with which to generate the required macroscopic quantum spatial superposition is a nanodiamond containing a negatively charged nitrogen vacancy (${\text{NV}}^{-}$) centre. In this review, methods to fabricate nanodiamonds containing ${\text{NV}}^{-}$ suitable for these quantum applications are discussed. The proposed probes of the macroscopic limits of quantum theory are presented along with the spin physics of the ${\text{NV}}^{-}$ centre relevant to those tests.