Electromechanical wavelength tuning of double-membrane photonic crystal cavities

We present a method for tuning the resonant wavelength of photonic crystal cavities (PCCs) around 1.55 μm. 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/blueshifting of the symmetric/antisymmetric 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. © 2011 American Institute of Physics.