Nanobenders as efficient piezoelectric actuators for widely tunable nanophotonics at CMOS-level voltages
Wentao Jiang, Felix M. Mayor, Rishi N. Patel, Timothy P. McKenna, Christopher J. Sarabalis, Amir H. Safavi‐Naeini
Abstract
Abstract Tuning and reconfiguring of nanophotonic components are needed to realize systems incorporating many components. The electrostatic force can deform a structure and tune its optical response. Despite the success of electrostatic actuators, they suffer from trade-offs between tuning voltage, tuning range, and on-chip area. Piezoelectric actuation could resolve these challenges, but only pm-per-volt scale wavelength tunability has been achieved. Here we propose and demonstrate compact piezoelectric actuators, called nanobenders, that transduce tens of nanometers per volt. By leveraging the non-uniform electric field from submicron electrodes, we generate bending of a piezoelectric nanobeam. Combined with a sliced photonic crystal cavity to sense displacement, we show tuning of an optical resonance by ~ 5 nm V −1 (0.6 THz V −1 ) and between 1520 ~ 1560 nm (~ 400 linewidths) within 4 V. Finally, we consider tunable nanophotonic components enabled by the nanobenders.