| 摘要 |
PURPOSE:To widen a wavelength range and a repetitive range of a short pulse row by optically connecting an amplification region, a light absorption region and an optical guide in series in the resonator direction and making the lifetime of a small number of carriers in the light absorption region smaller than the turnaround time of beams. CONSTITUTION:A laser is constituted in such a manner that ohmic-contact electrodes 25, 26 are attached to a four-layer double hetero-structure wafer in which n type InP 21, an InGaAsP active layer 22, p type InP 23 and p<+> type InGaAsP 24 are grown onto an n type InP substrate 20 in succession. The InGaAsP optical guide 27, absorption thereof to laser beams is small, is attached to the absorption region B. An optical resonator 28 is formed by the amplification region A and an optical guide region C. Forward DC currents are injected until laser oscillation is obtained as currents injected to the amplification region A, and forward currents of low density are injected or inverse voltage is applied to the light absorption region B and the lifetime of a small number of carriers in the light absorption region B is made smaller than time required for one reciprocation in the resonator 28 of beams. |
