Macroscopic Quantum Mechanics: Theory and Experimental Concepts of Optomechanics

TL;DR

This paper reviews theoretical techniques and experimental concepts in quantum optomechanics, focusing on preparing macroscopic objects in quantum states and testing quantum mechanics at large scales.

Contribution

It provides a comprehensive overview of measurement techniques and experimental proposals for demonstrating quantum phenomena in macroscopic mechanical systems.

Findings

Techniques for analyzing quantum measurement and state evolution.

Experimental concepts for demonstrating entanglement, teleportation, and Zeno effect.

Discussion of potential tests of quantum mechanics modifications involving gravity.

Abstract

Rapid experimental progress has recently allowed the use of light to prepare macroscopic mechanical objects into nearly pure quantum states. This research field of quantum optomechanics opens new doors toward testing quantum mechanics, and possibly other laws of physics, in new regimes. In the first part of this paper, I will review a set of techniques of quantum measurement theory that are often used to analyze quantum optomechanical systems. Some of these techniques were originally designed to analyze how a classical driving force passes through a quantum system, and can eventually be detected with optimal signal-to-noise ratio --- while others focus more on the quantum state evolution of a mechanical object under continuous monitoring. In the second part of this paper, I will review a set of experimental concepts that will demonstrate quantum mechanical behavior of macroscopic objects --- quantum entanglement, quantum teleportation, and the quantum Zeno effect. Taking the interplay between gravity and quantum mechanics as an example, I will review a set of speculations on how quantum mechanics can be modified for macroscopic objects, and how these speculations --- and their generalizations --- might be tested by optomechanics.