Quantum-optical tests of Planck-scale physics

TL;DR

This paper enhances cavity-optomechanical systems' precision for testing quantum gravity effects by developing advanced phase-space techniques, error analysis, and using squeezed states, making such tests more feasible with upcoming technology.

Contribution

It introduces improved phase-space paths, rigorous error analysis including photon number uncertainties, and a method employing squeezed light to increase measurement precision in optomechanical quantum gravity tests.

Findings

Enhanced accuracy in optomechanical measurements for quantum gravity tests.

Error analysis incorporating photon number fluctuations.

Robust scheme using squeezed states to improve precision.

Abstract

Recently it was proposed to use cavity-optomechanical systems to test for quantum gravity corrections to quantum canonical commutation relations [Nat. Phys. 8, 393-397 (2012)]. Improving the achievable precision of such devices represents a major challenge that we address with our present work. More specifically, we develop sophisticated paths in phase-space of such optomechanical system to obtain significantly improved accuracy and precision under contributions from higher-order corrections to the optomechanical Hamiltonian. An accurate estimate of the required number of experimental runs is presented based on a rigorous error analysis that accounts for mean photon number uncertainty, which can arise from classical fluctuations or from quantum shot noise in measurement. Furthermore, we propose a method to increase precision by using squeezed states of light. Finally, we demonstrate the robustness of our scheme to experimental imperfection, thereby improving the prospects of carrying out tests of quantum gravity with near-future optomechanical technology.