Electromechanical wavelength tuning of double-membrane photonic crystal cavities

TL;DR

This paper demonstrates a method for electromechanically tuning the resonant wavelength of double-membrane photonic crystal cavities around 1.55 μm by controlling membrane separation, achieving a 10 nm shift with low voltage.

Contribution

It introduces a novel electromechanical tuning approach for PCCs using double membranes and a fabrication method to prevent membrane sticking.

Findings

Achieved reversible wavelength tuning of 10 nm.

Controlled tuning with less than 6 V bias.

Confirmed electromechanical control through mode shifts.

Abstract

We present a method for tuning the resonant wavelength of photonic crystal cavities (PCCs) around 1.55 um. Large tuning of the PCC mode is enabled by electromechanically controlling the separation between two parallel InGaAsP membranes. A fabrication method to avoid sticking between the membranes is discussed. Reversible red/blue shifting of the symmetric/anti-symmetric modes has been observed, which provides clear evidence of the electromechanical tuning, and a maximum shift of 10 nm with < 6 V applied bias has been obtained.