Fast optical modulation of 10.6-µm radiation in GaAs waveguides by electrical injection

A GaAs p+-n-n+ diode has been used to study modulation of guided 1.15- and 10.6-μm radiation by electrical injection of free carriers. After irradiation with high-energy electrons to reduce the electron-hole recombination time, device rise and fall times in the nanosecond region are observed.