Radiation pressure, moving media, and multilayer systems

TL;DR

This paper develops a comprehensive theory of optical forces on moving multilayer dielectric systems, revealing velocity-dependent effects, polarization mixing, and their implications for nano-optomechanics and Casimir forces.

Contribution

It introduces a generalized transfer matrix approach to analyze optical forces on moving multilayer systems, highlighting polarization effects and velocity-dependent forces.

Findings

Velocity-dependent lateral and normal forces are derived.

Polarization mixing induces a velocity-dependent force sensitive to phase differences.

Polarization effects can cancel Doppler contributions, affecting force measurements.

Abstract

A general theory of optical forces on moving bodies is here developed in terms of generalized/4x4 transfer and scattering matrices. Results are presented for a planar dielectric multilayer of arbitrary refractive index placed in an otherwise empty space and moving parallel and perpendicular to the slab-vacuum interface. In both regimes of motion the resulting force comprises lateral and normal velocity-dependent components which may depend in a subtle way on the Doppler effect and TE-TM polarization mixing. For lateral displacements in particular, polarization mixing, which is here interpreted as an effective magneto-electric effect due to the reduced symmetry induced by the motion of the slab, gives rise to a velocity dependent force contribution that is sensitive to the phase difference between the two polarization amplitudes. This term gives rise to a rather peculiar optical response on the moving body and specific caseses are illustrated for incident radiation of arbitrarily directed linear polarization. The additional force due to polarization mixing may cancel to first order in V/c with the first order Doppler contribution yielding an overall vanishing of the velocity-dependent component of the force on the body. The above findings bare some relevance to modern developments of nano-optomechanics as well as to the problem of a frictional component to the Casimir force.