| 摘要 |
PURPOSE:To obtain a laser device having high resonance frequency and high light erasing ratio by substantially equalizing the thickness of an active layer to de Broglie wavelength of a carrier shorter than a resonator length 100mum. CONSTITUTION:A GaAs active layer 12 having 0.028mum of thickness of approximately de Broglie wavelength is formed on a semi-insulating GaAs film 11, interposed between an AlxGa1-xAs film 16, a p type Al0.47Ga0.53As film 18, a p type GaAs film 17 and an n type Al0.47Ga0.53As film 19, an n type GaAs film 20 for enclosing a light to continuously vary from 0.24 to 0.47 of composition (x), treated by RIE to form a resonator length 50mum, coated with an SiO2 film 21, and electrodes 22, 23 are attached. Since the thickness of the active film is near de Broglie wavelength, the state density function varies stepwisely by the quantum size effect, the energy width of the gain which contributes to the light emission is narrowed, the maximum gain is that much increased to decrease the threshold current density. A bias current density decreases even for high resonance frequency, and since the resonator length is short near the de Broglie wavelength of the thickness of the active layer, heating due to the parasitic resistance of the laser is less. |
