Demonstration of 25 Gb/s NRZ modulated 1.3 $\mu\mathrm{m}$ surface-emitting D FB lasers

We present a 1.3 $\mu\mathrm{m}$ surface-emitting DFB laser with second order grating and double section ridge waveguide. The lasers can achieve stable single mode operation with threshold current 13.5 mA, and 25 Gb/s modulation rates.

1. Introduction

Semiconductor laser has high efficiency, high coherence and perfect stability and is widely used in optical communication system, pump source system and so on [1], [2]. Owing to the advantages of easy formation of two-dimension arrays and hybrid integration with silicon platform, surface emitting laser has attracted great attention. Vertical cavity surface-emitting laser (VCSEL), a typical solution of surface emission, can extract light efficiently and has low power consumption [3], [4]. But, the realization of VCSEL at long wavelength has been hindered due to the poor property of DBR materials. Grating coupled surface emitting distributed feedback (SEDFB) laser, another type of surface emitting laser, has obtain widespread application due to its characteristic of single mode, long wavelength and high speed modulation [5], [6].