Ultra low RIN, low threshold AlGaInAs/InP BH-DFB laser

Abstract

This study presents a comparative analysis of DFB lasers based on AlGaInAs/InP heterostructures, exploring the impact of different groove shapes and cavity lengths on laser output characteristics. Leveraging the vertical groove structure, we achieved a remarkable laser output of 90mW at 25°C. Compared to lasers without grooves, this represents a 3.6-fold increase in output power, coupled with an impressively low threshold current of only 4mA. In addition, we conducted a study on the temperature stability of the laser, revealing that even at elevated temperatures of 85°C, the laser maintains an edge mode suppression ratio of over 45dB. This demonstrates the robustness and reliability of the laser over a wide range of operating conditions, further enhancing its suitability for practical applications in diverse environments. Upon packaging the chip into a butterfly shape, we observed a significant reduction in relative intensity noise, with values below -162.8 dB/Hz across the frequency range of 0-40 GHz, while operating at an output power of 3mW. These findings underscore the robustness, reliability, and high-performance capabilities of the developed DFB laser, highlighting its potential for various practical applications.