Designing evanescent optical interactions to control the expression of Casimir forces in optomechanical structures

TL;DR

This paper introduces an optomechanical system that uses resonant optical forces to control and measure Casimir forces in a layered silicon structure, enabling all-optical manipulation of quantum fluctuation effects.

Contribution

It presents a novel design of a photonic-crystal membrane system that employs optical forces to modulate Casimir effects without altering the force directly.

Findings

Optical forces can control Casimir force effects in the membrane.

The system allows for precise measurement of Casimir forces via optical reflection spectra.

Optical modulation can switch the dominance of Casimir physics in the device.

Abstract

We propose an optomechanical structure consisting of a photonic-crystal (holey) membrane suspended above a layered silicon-on-insulator substrate in which resonant bonding/antibonding optical forces created by externally incident light from above enable all-optical control and actuation of stiction effects induced by the Casimir force. In this way, one can control how the Casimir force is expressed in the mechanical dynamics of the membrane, not by changing the Casimir force directly but by optically modifying the geometry and counteracting the mechanical spring constant to bring the system in or out of regimes where Casimir physics dominate. The same optical response (reflection spectrum) of the membrane to the incident light can be exploited to accurately measure the effects of the Casimir force on the equilibrium separation of the membrane.