Enhancing Wavelength Tunability of Photonic Crystal Nanolasers by Waveguide-Like Strain Shapers

In this report, we propose an idea of connecting 1D photonic crystal (PhC) nanocavity with novel waveguide-like strain shapers in a polydimethylsiloxane substrate. In theory, the induced film-edge strain by the strain shapers can significantly enhance the wavelength tunability of PhC nanocavity under different applied stress. By our nanofabrication process, we realize this idea in the form of a tunable nanolaser. In experiments, the nanolaser shows the enhanced wavelength tunability both under stretching and compressive stress. By investigating the effects of PhC periods and length of the strain shapers, we obtain an optimized lasing wavelength tunability of-13.9 nm under every percentage strain variation in experiments. When further taking the 2nd-order mode in the nanocavity into consideration, we observe a wide lasing wavelength tuning range over 160 nm, which takes only the applied strain \Delta \xi {tot} of ±0.05. In addition to the large wavelength response beneficial for tunable nanolasers and optical strain sensors, we also believe that this waveguide-like strain shapers can serve as the optical interconnections at the same time in the flexible photonic circuits.