| 摘要 |
PURPOSE:To make an oscillating mode to agree with a specified wavelength, by providing two corrugations having the different periods, and determining the periods of the corrugations so as to satisfy specified relation. CONSTITUTION:Corrugations having the periods of A1 and A2 are provided between upper and lower clad layers 2 and 6 holding an active layer 4 and an n-type guide layer 3 and a p-type guide layer 5. When the wavelength of a mode (+1) at the right of a wavelength lambdaB1 determined by the corrugation 1 agrees with the wavelength of a mode (-1) at the right of a wavelength lambdaB2 determined by the corrugation 2, there is relation of A1<-1>-A2<-1>=L<-1> between the periods A1 and A2 of both corrugations and a length L of a resonator. When the periods of two corrugations are determined as A1<A2 in order to satisfy said relation, the + first mode of the corrugation on the side A1 agrees with the - first mode on the side of A2. Since the oscillating threshold value of this mode is largely decreased, the single mode oscillation is implemented. |
