SEMICONDUCTOR OPTICAL AMPLIFIER, ASE RADIATING OPTICAL SOURCE, OPTICAL GATE ARRAY, VARIABLE WAVELENGTH LASER, MULTI-WAVELENGTH LASER AND OPTICAL TRANSMISSION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor optical amplifier which is suited for laser beam in 1.2-1.6 nm bands suited for a long distance large-capacity transmission over quartz type optical fibers and little in variation of an optical amplification factor at an environmental temperature. SOLUTION: The semiconductor optical amplifier comprises an n-type Al0.4 Ga0.6 As clad layer 102, a lower GaAs optical waveguide layer 103, a GaInNAs/GaAs multiple quantum well active layer 104, an upper GaAs guide layer 105 and a first p-type Ga0.5 In0.5 P clad layer 106 laminated in this order on an n-type GaAs substrate 101.