External Control of Dissipative Coupling in a Heterogeneously Integrated Photonic Crystal—SOI Waveguide Optomechanical System

Viktor Tsvirkun,Isabelle Robert-Philip,Fabrice Raineri,Isabelle Sagnes,Alessandro Surrente,Grégoire Beaudoin,Rama Raj,Rémy Braive

doi:10.3390/photonics3040052

Abstract

Cavity optomechanical systems with an enhanced coupling between mechanical motion and electromagnetic radiation have permitted the investigation of many novel physical effects. The optomechanical coupling in the majority of these systems is of dispersive nature: the cavity resonance frequency is modulated by the vibrations of the mechanical oscillator. Dissipative optomechanical interaction, where the photon lifetime in the cavity is modulated by the mechanical motion, has recently attracted considerable interest and opens new avenues in optomechanical control and sensing. In this work we demonstrate an external optical control over the dissipative optomechanical coupling strength mediated by the modulation of the absorption of a quantum dot layer in a hybrid optomechanical system. Such control enhances the capability of tailoring the optomechanical coupling of our platform, which can be used in complement to the previously demonstrated control of the relative (dispersive to dissipative) coupling strength via the geometry of the integrated access waveguide.

Highlights

Semiconductor nano-optomechanical systems have shown a rapid progress over the last years, with the demonstration of record optomechanical couplings, mechanical frequencies in the GHz range and above, and a well-controlled optical and mechanical dissipation [1]
By introducing a non-resonant pump source, we achieve a deterministic modulation of the optical losses of the cavity induced by the quantum dots (QDs) absorption at frequencies close to the cavity resonance. We show that this optical modulation is sensitive to the mechanical motion of the device, coupled to the optical cavity resonance via an optomechanical interaction
Pattern transfer of the photonic crystal (PhC) and mesa structures onto the latter is achieved via electron-beam lithography (EBL), reactive ion etching and inductively coupled plasma etching

Summary

Introduction

Semiconductor nano-optomechanical systems have shown a rapid progress over the last years, with the demonstration of record optomechanical couplings, mechanical frequencies in the GHz range and above, and a well-controlled optical and mechanical dissipation [1]. Dissipative coupling may significantly enhance the detection sensitivity in optomechanically-based sensing schemes [8,9] It could open new possibilities in the optomechanical control of systems featuring both types of coupling mechanisms [10,11], where a tailored coupling strength is highly desirable. Such tailoring was demonstrated using external [3] or integrated [6] variation of the geometry of the optical access channel to the nanocavity. We propose the possibility of exerting an external optical control exclusively of the intrinsic dissipative component of the optomechanical coupling within a hybrid optomechanical system by making use of a layer

Methods

Results

Conclusion