Acoustically tuneable optical transmission through a subwavelength hole with a bubble

TL;DR

This paper demonstrates theoretically how ultrasound-driven bubble pulsations can modulate light transmission through a subwavelength water-filled hole, enabling tunable acousto-optic control at nanoscale.

Contribution

It introduces a novel method for controlling light with ultrasound in subwavelength structures using bubble pulsations to modulate refractive index.

Findings

Ultrasound-driven bubble pulsations modulate light transmission.

Spectral tuning achieved through bubble pulsations.

Potential applications in tunable metamaterials and ultrasound transduction.

Abstract

Efficient manipulation of light with sound in subwavelength-sized volumes is important for applications in photonics, phononics and biophysics, but remains elusive. We theoretically demonstrate the control of light with MHz-range ultrasound in a subwavelength, 300 nm wide water-filled hole with a 100 nm radius air bubble. Ultrasound-driven pulsations of the bubble modulate the effective refractive index of the hole aperture, which gives rise to spectral tuning of light transmission through the hole. This control mechanism opens up novel opportunities for tuneable acousto-optic and optomechanical metamaterials, and all-optical ultrasound transduction.