Near-Field Dynamics of Ultra-Wide-Aperture (800 μ m) Diode Lasers Under Nanosecond Pulse Excitation

We present a study of near-field dynamics of ultra-wide-aperture (800 $\mu \text{m}$ ) high-power diode lasers pumped by nanosecond current pulses. The studied lasers are based on AlGaAs/InGaAs/GaAs asymmetric heterostructure with a wide waveguide and operate at 1060 nm. It is shown that an increased aperture width of 800 $\mu \text{m}$ makes it possible to maintain high emission efficiency at high currents for 3 ns pulses. It is determined that lasing turn-on delay is inhomogeneous along the aperture. Initial turn-on occurs at the edges, while the delay near the aperture center reaches 180–450 ps depending on resonator length and current amplitude. For instance, resonator lengths over 2.5 mm and current amplitude of 90 A correspond to turn-on delay of 200 ps.