Derivation of the Spectral Width of a 0.8μm AlGaAs Laser Considering 1/f Noise

The spectral profile of a CSP-type 0.8 μm AlGaAs laser and its spectral width (FWHM) were estimated from experimental results on the lasers FM noise at room temperature. The power-independent spectral width was also derived from the recently-reported power-independent 1/f noise. The result was 2.0 MHz, which agrees well with previous experimental results. The power-dependent width \varDeltaν was also derived as 2.0 MHz<\varDeltaν≤q}8.8 MHz for 0{<(I/I_th-1)^-1{≤q}7, where I and I_th represent the injection current and its threshold value, respectively.