Recirculation-enhanced switching in photonic crystal Mach-Zehnder interferometers

Abstract

Abstract:We show that Mach-Zehnder interferometers (MZIs) formed from waveguides in a perfectly reflecting cladding can display manifestly different transmission characteristics to conventional MZIs due to mode recirculation and resonant reflection. Understanding and exploiting this behavior, rather than avoiding it, may lead to improved performance of photonic crystal (PC) based MZIs, for which cladding radiation is forbidden for frequencies within a photonic bandgap. Mode recirculation in such devices can result in a significantly sharper switching response than in conventional interferometers. A simple and accurate analytic model is presented and we propose specific PC structures with both high and low refractive index backgrounds that display these properties. 123,901 (2003). 18. P. Lalanne, S. Mias, and J. P. Hugonin, "Two physical mechanisms for boosting the quality factor to cavity volume ratio of photonic crystal microcavities," Opt. Express 12, 458-467 (2004). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-12-3-458.

Manipulation of the resonance interaction in Mach-Zehnder-Fano interferometers

“…Such modes are the standing waves formed in two arms. Therefore, the transmission is blocked, and a very large Q factor can be anticipated due to the mode symmetry mismatch [29]. At the same time, the total intensity in the arm builds up due to the freezing of the waves.…”

Design of a photonic crystal differential phase comparator for a Mach–Zehnder switch

“…Many researchers have focused their research on PC MZIs [1][2][3][4][5][6]. In [2,3] simple MZI structures were reported.…”