Amplitude-modulation characteristics of barrier-reservoir and quantum-well electron-transfer (BRAQWET) modulators

We have studied theoretically and experimentally the intensity-modulation characteristics of GaAs-based light modulators based on the barrier-reservoir and quantum-well electron-transfer (BRAQWET) structure. The transmission-voltage characteristics are nonlinear and follow an inverse exponential relationship which is derived herein. It is also seen that a multiple-period BRAQWET structure is unnecessary and partially ineffective for amplitude modulation and that a one-period BRAQWET structure can give comparable results while providing more versatility for the device design. Al/sub x/Ga/sub 1-x/As-based guided-wave modulators are demonstrated with a 50% modulation index at a drive voltage of 1 V.