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 feed-back of lateral resonant modes.Under a large continuous-wave operation,the maximum output power of laser device is 43.03 W,about 1 W higher than that of the standard broad-area laser at 48 A.