Improvement of the dynamic input power range in a 10 Gb s⁻¹all-optical Mach–Zehnder interferometric wavelength converter module with monolithically integrated SOA preamplifiers and tapered-edge multimode interference couplers

Abstract

All-optical wavelength conversion at 10 Gb s −1 is demonstrated in a Mach-Zehnder interferometric wavelength converter (MZI-WC) module with monolithically integrated SOA preamplifiers and tapered-edge multimode interference couplers (TMMIs). A conventional buried-type 1 × 2 MMI coupler exhibits a minimal excess loss of 0.43 dB and a reflectivity of 5.1 × 10 −4 (L MMI = 172 µm, W MMI = 12 µm). We adapt the 1 × 2 TMMI in the MZI-WC to improve back-reflection and poor uniformity, which is a major problem of conventional MMI and Y-branch. A good performance of the MZI-WC monolithically integrated with TMMI and SOA preamplifiers at 10 Gb s −1 is obtained with clear eye patterns, and a power penalty below 1.5 dB at a 10 −9 bit error rate over the whole C band (45 nm span) is obtained. The dynamic input power range is enhanced up to 11.3 dB by adjusting only the injection current of the SOA preamplifier.

Integrated twin modulator switches through MMI splitting and electroabsorption modulation

“…Using a modified buried ridge stripe (BRS) structure, an MZI interferometric wavelength mode converter was integrated with an SOA preamplifier and a tapered-edge MMI coupler [3]. Device integration can also be implemented via selective-area-growth (SAG), a technique that diversifies bandgap energies in selected areas during growth, such as modulators integrated to lasers [4].…”