Discretization Effects of Digital Control of Thermally Tunable 2×2 MZI Couplers
Iman Zand, Wim Bogaerts · 2019
We describe how digital voltage driving of tunable 2×2 Mach-Zehnder couplers with thermo-optic phase shifters introduces discretization errors which significantly affect programmable photonic circuits. Performing quantitative analysis, we show that proper biasing of couplers and simultaneous driving of arms can improve discretization errors.