High peak power mini-array quantum cascade lasers operating in pulsed mode at room temperature

Mini-array quantum cascade lasers (MA-QCLs) present an effective strategy to mitigate the thermal limitations inherent to broad-area devices, yet their peak power has remained constrained. In this work, we demonstrate a high-power MA-QCL emitting at around 4.6µm, featuring an optimized micro-ridge geometry that significantly enhances heat dissipation. The device, comprising 20 micro-ridges with a total width of 400 µm, achieves a peak output power of 356 W at room temperature under pulsed operation (1 µs, 1 kHz), along with a maximum wall-plug efficiency (WPE) of 15.58 %. Moreover, the laser maintains a stable near-Gaussian far-field profile, with full-width-at-half-maximum divergence angles of 29.2° (slow axis) and 40.4° (fast axis) at a driving current of 140 A. Collectively, these results position MA-QCLs as a compelling platform for achieving high peak power from single-emitter mid-infrared lasers.