Mechanically tunable ultrananocrystalline diamond 1D photonic crystal slab

Abstract

Diamond is considered a promising platform for power-semiconductor, photonic, mechanical, and quantum devices owing to its exceptional material properties, including the existence of optically active color centers. In particular, diamond photonic crystals have attracted significant attention and have been tailored primally aimed at enhancing the luminescence from these color centers. Photonic crystals provide strong optical confinement through their high-quality resonances; however, because they are highly sensitive to fabrication deviations that shift the resonant wavelength, a practical and broadly applicable strategy for tuning the optical modes is required. In this study, we demonstrate a mechanically tunable ultrananocrystalline diamond (UNCD) one-dimensional (1D) photonic crystal (PhC) slab and the mechanical tuning of its optical response. The UNCD 1D PhC slab is integrated with electrostatic submicron-comb drive UNCD actuators, which modulate the optical response by mechanically tuning the period from 1004 nm to 1076 nm with an acceptable driving voltage of 75 V. This period modulation alters the guided modes of the UNCD 1D PhC slab, consequently shifting the resonant wavelength and the corresponding reflection peak from 1031 nm to 1054 nm in TE polarization. The underlying concept and tuning mechanism are independent of the crystalline form of diamond. These results establish a new tuning strategy for diamond photonic devices and open up new possibilities for their applications.