Low-loss, low-cross-talk crossings for silicon-on-insulator nanophotonic waveguides

Opt Lett. 2007 Oct 1;32(19):2801-3. doi: 10.1364/ol.32.002801.

Abstract

We present compact crossings for silicon-on-insulator photonic wires. The waveguides are broadened using a 3 microm parabolic taper in each arm. By locally applying a lower index contrast using a double-etch technique, loss of confinement is reduced and 97.5% transmission (-1.7 dB) is achieved with only -40 dB cross talk.