A SEMICONDUCTOR WAVE-GUIDE-TYPE OPTICAL FREQUENCY SHIFTER

A waveguide-type optical frequency shifter based on a rotating half-wave plate is proposed. The underlying principle can be used to realize a bit-rate-free and modulation-code-free optical frequency shifter. The waveguide was formed along the [111] direction on a GaAs (110) substrate by molecular beam epitaxy (MBE) and reactive ion beam etching (RIBE). A 10-MHz optical frequency shift with 16 V-p-p applied voltage and 22.5% shift efficiency is demonstrated.