Arrays of vertical-cavity electroabsorption modulators for parallel signal processing

Abstract

Vertical-cavity multiple quantum well electroabsorption modulators (EAM) offer gigahertz modulation speeds, insensitivity to light polarisation and can be integrated into large arrays. They are therefore good candidates for efficient parallel signal processing architectures. We present high-performance 2 x 128 and 2 x 64 EAM arrays that were fabricated at 4'' wafer-scale by using optimised fabrication and hybridisation processes. The arrays exhibit contrast ratios of 20:1 with a voltage swing of 1 V, a maximum contrast ratio of 335:1 for a 10 V bias and a modulation frequency in excess of 15 MHz.