| 摘要 |
PROBLEM TO BE SOLVED: To create a reflective digitally tunable laser by a method, wherein a multi-quantum well material for forming a passive wave guide and a multi- quantum well material for forming an optical amplifier are deposited by single growth. SOLUTION: A multi-quantum well material 26b of first type which is suitable for forming a passive waveguide and a multi-quantum well material 26a of a second type, suitable for forming an optical amplifier are deposited by single growth. Next, the multi-quantum well material 26b of first type is pattern- formed in a plurality of input waveguides connected with a wavelength selection device, and the multi-quantum well material 26a of second type is pattern- forming into at least the two controllable optical amplifiers. Next, in order to form first and second facet mirrors, a semiconductor substrate is cleaved at two positions apart from each other. Thereafter, at least two electrodes are deposited, and a bias current can be selectively supplied to one of at least the two controllable optical amplifiers. |
