Investigation of the quasi-cw heating dynamics of an active region of high-power semiconductor lasers (λ = 1060 nm) with an ultra-wide emitting aperture (800 μm)

An approach has been developed to study temporal behaviour of the active region overheating in high-power semiconductor lasers (λ = 1060 nm) with an ultra-wide aperture (800 μm) operating in a quasi-continuous regime of pumping by current pulses with an amplitude of 21 A, a duration of 1 ms, and a repetition rate of 10 Hz. The approach is based on measuring the lasing dynamics with spectral selection. The lasing spectrum analysis shows that the region of the rising edge, where the amplitude of the current pulse increases, is characterised by a maximum red-shift rate of 30 nm·ms^–1, which is due to both thermal and nonthermal effects. The pulse region corresponding to a constant pump current amplitude is characterised only by a thermal red shift of the lasing spectrum long-wavelength edge at a rate of ∼1 nm·ms^–1. The obtained experimental active region overheating is 2.78°C for the constant pump current amplitude region, which agrees with the calculated overheating of 3.08°C for the pump conditions under study.