Electrically pumped widely tunable O-band hybrid lithium niobite/III-V laser
Ya Han, Xian Zhang, Fujin Huang, Xiaoyue Liu, Mengyue Xu, Zhongjin Lin, Mingbo He, Siyuan Yu, Ruijun Wang, Xinlun Cai
Abstract
Significant improvements in the lithium niobate on insulator (LNOI) platform are pushing LNOI-based laser sources to the forefront of integrated photonics. Here, we report the first, to the best of our knowledge, electrically pumped hybrid lithium niobate/III-V laser by butt coupling an InP-based optical gain chip with a LNOI photonic integrated circuit (PIC). In the PIC, a Vernier filter consisting of two LNOI microring resonators is employed to select the lasing wavelength. A wavelength tuning range of more than 36 nm is achieved in the O band. The hybrid laser has a maximum on-chip optical power of 2.5 mW and threshold current density of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mn>2.5</mml:mn> <mml:mspace width="thickmathspace"/> <mml:msup> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mi mathvariant="normal">k</mml:mi> <mml:mi mathvariant="normal">A</mml:mi> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mo>/</mml:mo> </mml:mrow> <mml:mi mathvariant="normal">c</mml:mi> <mml:mi mathvariant="normal">m</mml:mi> </mml:mrow> <mml:mn>2</mml:mn> </mml:msup> </mml:math> . A side mode suppression ratio better than 60 dB is achieved.