We present a powerful design and optimization method for devices in a photonic crystal. The method is based on a Wannier basis field expansion and efficient matrix analysis techniques for searching through a vast number of designs. The method permits the design of many compact optical devices with complex and novel functions. We present a design example of a very compact mode separator that is 8.2 µm × 13.3 µm in size that demultiplexes the three modes of an input photonic crystal multimode waveguide into three single-mode output waveguides. We verify the method with finite-difference time-domain calculations.
© 2005 Optical Society of America
(000.3860) General : Mathematical methods in physics
(130.3120) Integrated optics : Integrated optics devices
(230.3990) Optical devices : Micro-optical devices
(260.2110) Physical optics : Electromagnetic optics
Yang Jiao, Shanhui Fan, and David A. B. Miller, "Demonstration of systematic photonic crystal device design and optimization by low-rank adjustments: an extremely compact mode separator," Opt. Lett. 30, 141-143 (2005)