Improving the performance of high-power broad-area lasers by suppressing cavity modes propagating in the lateral dimension

We first study the effect of cavity modes propagating in the lateral dimension on high-power semiconductor lasers with a large stripe width. A sidewall microstructure was fabricated to prevent optical feedback of lateral resonant modes.Theoretically, we demonstrate the existence of lateral resonant modes in the Fabry–Perot cavity with a large stripe width.Experimentally, we design the corresponding devices and compare them with conventional broad-area diode lasers. About a 15% reduction in threshold current and a 27% increase in maximum electro-optical conversion efficiency are achieved. The amplified spontaneous emission spectrum is narrowed, which proves that lateral microstructures suppress optical feedback of lateral resonant modes. Under a large continuous-wave operation, the maximum output power of laser device is43.03 W, about 1 W higher than that of the standard broad-area laser at 48 A.