Polarization-recycling phase tuning in an integrated ring resonator.

The necessity for efficient optical phase tuning has long been critical and is increasingly urgent in light of system scaling and growing demands of data transmission. In an integrated ring resonator, the design freedom for high efficiency is even more constrained due to its ultra-compact footprint and low cross talk requirements for large-scale operation. In this Letter, we demonstrated a polarization multiplexed microring resonator for efficient phase tuning. Experimental results indicate 55%/177% enhancement in the phase tuning efficiency compared with traditional devices operated in a pure TE/TM mode. With zero change in the fabrication process, the proposed structure provides a versatile design methodology for efficiency enhancement in the realm of data communications and optical computing.