| 摘要 |
PURPOSE:To enable improvement in modulating sensitivity by noticing that the interaction between free electron or hole and light increases with an increase in wavelength and transmitting the light to be modulated through the inside of a semicondcutor sample in a resonator to change the density of the hole. CONSTITUTION:Light Pi to be modulated is made incident through a window having a dielectric multilayered film 5 on the left side and a forward voltage is impressed through an ohmic electrode 4 to the p-n junction between a carrier confinement layer 2 and a high density layer 3. The high density carrier of the layer 3 is injected into the layer 2 and the carrier density in the layer 2 is largely changed, as the effect of said voltage impression. The amplitude and phase of the light Pi are consequently modulated by the change in the carrier density of the layer 2. If the distance between the resonators is adjusted to a prescribed value, the reflected light Pr taken out to the outside near the sharp resonance peak of the resonator is subjected to the much intensified amplitude and phase modulation by the resonance effect. As a result, the modulator for IR light or far IR light having a small size, high efficiency and high speed is realized. |
