We demonstrate tuning of double-coupled one-dimensional photonic crystal cavities by their out-of-plane nanomechanical deformations. The coupled cavities are pulled by the vertical electrostatic force generated by the potential difference between the device layer and the handle layer in a silicon-on-insulator chip, and the induced deformations are analyzed by the finite element method. Applied with a voltage of 12 V, the cavities obtain a redshift of 0.0405 nm (twice the linewidth) for their second-order odd resonance mode and a blueshift of 0.0635 nm (three times the linewidth) for their second-order even resonance mode, which are mainly attributed to out-of-plane relative displacement. Out-of-plane tuning of coupled cavities does not need actuators and corresponding circuits; thus the device is succinct and compact. This working principle can be potentially applied in chip-level optoelectronic devices, such as sensors, switches, routers, and tunable filters.
© 2013 Optical Society of America
Original Manuscript: April 9, 2013
Manuscript Accepted: May 7, 2013
Published: June 3, 2013
Feng Tian, Guangya Zhou, Yu Du, Fook Siong Chau, Jie Deng, and Ramam Akkipeddi, "Out-of-plane nanomechanical tuning of double-coupled one-dimensional photonic crystal cavities," Opt. Lett. 38, 2005-2007 (2013)