We investigated negative refraction and subwavelength imaging by a mechanically tunable photonic crystal (PC) slab. A honeycomb-structured PC composed of a silicon-polyimide membrane was used because it exhibits isotropic negative refraction within the second photonic band. Using the finite-difference time-domain (FDTD) method, we demonstrated focusing properties of the PC lenses at various frequencies and mechanical stresses. Analyses based on a ray optics model and equifrequency surface also confirmed the behavior observed by the FDTD simulations. These results suggested a mechanically tunable superlens, whose achievable frequency bandwidth was 12.9% of the center frequency for a mechanical stress of ±10%.
© 2006 Optical Society of America
Original Manuscript: July 18, 2005
Revised Manuscript: September 13, 2005
Manuscript Accepted: September 22, 2005
Vol. 1, Iss. 4 Virtual Journal for Biomedical Optics
Qi Wu, Ethan Schonbrun, and Wounjhang Park, "Tunable superlensing by a mechanically controlled photonic crystal," J. Opt. Soc. Am. B 23, 479-484 (2006)