METHOD FOR DESIGNING SEMICONDUCTOR LASER DEVICE, DESIGNING METHOD FOR RAMAN AMPLIFIER, MANUFACTURING METHOD FOR SEMICONDUCTOR LASER DEVICE, SEMICONDUCTOR LASER DEVICE, RAMAN AMPLIFIER, AND OPTICAL COMMUNICATION SYSTEM

摘要

A method for designing a semiconductor laser device comprises selecting a semiconductor laser device capable of fast switching between FBG and FP modes and using the semiconductor laser device in a manner that the device oscillates in coherent collapse mode. Where, the semiconductor laser device has an LFF cycle set equal to or below 20 ns by controlling a distance from an output-side reflection means to a second reflection means, and an effective return light quantity (κ) to a semiconductor laser element defined as the following expression: κ = (1 / τ) × (1 - R₁) × (R₂ / R₁)^½ Where, τ represents the circulation time of light in the semiconductor laser element; R₁ represents the reflectance of the output-side reflection means; and R₂ represents the reflectance of the second reflection means.