Abstract

There has been considerable recent interest in external optical modulators [1]-[5]. MQW optical modulators with more than a 40 GHz modulation bandwidth and 7 V driving voltage at a 1.54 μm wavelength have been reported by the authors [5]. However, the insertion loss was too high due to the large coupling loss caused by small spotsize (<0.4 μ m) in the vertical direction.

© 1990 Optical Society of America