Add-drop filter based on dual photonic crystal nanobeam cavities in push-pull mode

TL;DR

This paper presents a novel four-port add-drop filter using dual photonic crystal nanobeam cavities on a standard SOI CMOS chip, achieving high extinction and bandwidth without process modifications.

Contribution

First implementation of a four-port add-drop filter based on photonic crystal nanobeam cavities on a commercial CMOS platform.

Findings

16dB extinction in through port

1dB loss in drop port

64GHz 3dB bandwidth

Abstract

We demonstrate an add-drop filter based on a dual photonic crystal nanobeam cavity system that emulates the operation of a traveling-wave resonator and drops light on resonance to a single output port. Realized on an advanced SOI CMOS (IBM 45nm SOI) chip without any foundry process modifications, the device shows 16dB extinction in through port and 1dB loss in drop port with a 3dB bandwidth of 64GHz. To the best of our knowledge, this is the first implementation of a four-port add-drop filter based on photonic crystal nanobeam cavities.