Reconfigurable photonic crystal resonator generated from Gaussian photonic potential well

We propose and demonstrate reconfigurable photonic crystal (PhC) resonators. In this generic configuration, the position and size of a PhC resonator can be defined (and redefined) repeatedly as simply relocating a curved microfiber along the linear PhC waveguide. In the proximity of the PhC waveguide in contact with the microfiber, the cutoff frequency (effective index) of the PhC waveguide becomes smaller (larger) than that of a bare PhC waveguide. Accordingly, when a curved microfiber is in contact with the PhC waveguide, a linear PhC resonator having Gaussian-shaped photonic potential well is formed. Experimentally we confirm the characteristics of reconfigurable PhC resonators by observing the laser operations and the transmission dips slightly below the bandedge mode.