Narrow-Linewidth Semiconductor Laser With High-Order Sidewall Gratings
Yuanbo Xu, Mingjin Wang, Hongwei Qu, Wenzhen Liu, Ting Fu, Jing Li, Fangling Du, Wanhua Zheng
Abstract
We demonstrate a kind of ridge waveguide semiconductor laser with high-order sidewall gratings around 1550 nm. The ridge waveguide with 11th-order sidewall gratings is fabricated by the standard contact-types <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$i$ </tex-math></inline-formula> -line lithography. The fabricated device shows an output power of 44 mW at a bias current of 500 mA and a stable single-mode operation over wide ranges of current and temperature conditions. A high side-mode suppression ratio ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sim 59$ </tex-math></inline-formula> dB), a narrow linewidth of 63 kHz and a low relative intensity noise ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$ < -150$ </tex-math></inline-formula> dB/Hz under the frequency range from 0.03 to 20 GHz) have been demonstrated at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$25^{\circ }\text{C}$ </tex-math></inline-formula> .