Inducing forced and auto-oscillations in one-dimensional photonic crystals with light

Abstract

© The Authors. Published by SPIE. We induced forced and auto-oscillations in one-dimensional photonic crystals (1-D-PCs) with localized defects when light impinges transversally to the defect layer. The photonic structure used consists of a microcavity-like structure formed of two 1-D-PCs made of free-standing porous silicon, separated by a variable air gap (the defect) and the working wavelength is 633 nm. The force generation was made evident by driving a laser light by means of a chopper; the light hit the photonic structure and induced a vibration and the vibration was characterized by using a very sensitive vibrometer. For example, we measured peak displacements and velocities ranging from 2 to 167 μm and 0.4 to 2.1 mm/s with a power light level from 2.6 to 13 mW. In comparison, recent evidence showed that giant resonant light forces could induce average velocity values of 0.45 mm/s in microspheres embedded in water with a 43-mW light power.