Lithographic and optical tuning of InGaAsP membrane photonic crystal nanocavities with embedded InAs quantum dots

Hexagonal symmetry InGaAsP membrane type cavities with embedded InAs quantum dots as active emitters were investigated by room temperature photoluminescence experiments at wavelengths near 1.50 µm. Cavities consisting of simple defects of just removing one or seven air holes were studied as well as modified cavities with additional holes decreased in size and shifted in position. The latter include the H0 cavity, in which only two adjacent holes were modified, but none removed. Low-Q cavity modes were observed after modification of the surrounding holes. The resonant frequencies were varied over a large range of lithographic parameters both by changing the lattice spacing or the size of the modified holes. More than 15 nm reversible dynamic optical tuning of the resonance modes was observed by changing the applied laser power up to 5 mW. For thermo-optic tuning, this corresponds to a heating of up to 200 °C.