Abstract

Over the last fifteen years, various types of semiconductor electro-absorption modulators have been fabricated and analysed. The potential use of such devices in photonic switching fabrics and inter-chip interconnections has provoked numerous studies of their performance capabilities and design trade-offs [1,2]. Of particular concern has been the impossibility, until recently, to manufacture fast 2-D multiple quantum well (MQW) phase modulator arrays. Trezza and coworkers reported a π-phase change in a reflection-mode vertical cavity asymmetric multiple quantum well [3], in which the absorption variation induced by an external applied field causes a change in the dominant role played by one of the cavity minors. Moreover, the device, named a phase-flip modulator, is designed so that no change in throughput is induced by the bias voltage. The π phase change at constant reflectivity requires a careful cavity design and the precise determination of the operating wavelength and voltage swing. A systematic study demands the implementation of a tolerance methodology. Results, based on such a methodology, will be presented that analyse which parameters are in achieving the best overall device performance, the optimum operating conditions and the higher degree of robustness (the tolerance) to the variations in device characteristics.

© 1997 Optical Society of America