SEMICONDUCTOR QUANTUM WELL OPTICAL MODULATOR AND OPTICAL MODULATION METHOD AND DEVICE USING THE SAME

摘要

PURPOSE: To provide a semiconductor quantum well type optical modulator with which a large absorption change and refractive index change is obtainable with a small voltage and which has high performance and an optical modulation method and device using the same. CONSTITUTION: An n-InP clad layer 2, multiple quantum well layers 3 consisting of non-doped InGaAsP/InGaAsP (stress is compensated), a p-InP clad layer 4 and n-InP and p-InGaAs layers 5 are successively laminated on an n-InP substrate 1. The rear surface of this n-InP substrate 1 is provided with an N side electrode 6 and a P side electrode 7 on the p-InGaAs layer 5. A lead wire 8 for electric field impression is connected on the P side electrode 7. Incident light 9 is emitted as modulating light 10. Since the absorption peak of TM polarized light is set higher than the absorption peak for TE polarized light, this optical modulator operates as the high-performance optical modulator if the modulation operation is executed by the TM polarized light.