| 摘要 |
PROBLEM TO BE SOLVED: To amplify a signal light having nearby wavelength of that of a laser oscillation light by outputting only an amplified signal light, without the use of an optical filter in a optical amplifier using an operational principle of a traditional gain clamp semiconductor optical amplifier. SOLUTION: A laser oscillates at a wavelength ofλ0 by inserting gain regions in the two-arm waveguides 13a and 13b of a symmetrical Mach-Zehnder interferometer, comprises a light reflection means reflecting a light of the wavelengthλ0 at an input and an output ports, cross ports of the symmetrical Mach-Zehnder interferometer, forms a laser resonator with the light reflection means and the gain region, and causes laser oscillation of wavelengthλ0. A light of the wavelengthλs is introduced from a port with no light reflection means connected and amplified in the gain regions 14a, 14b with the signal gain clamped in the state of laser oscillation threthold, and the amplified signal light is separated from the laser oscillation light and output from a different port. |
