Open AccessPhotolithography allows high-Q AlN microresonators for near octave-spanning frequency comb and harmonic generation
Author(s) -
Jia Liu,
Hai-Zhong Weng,
Adnan Ali Afridi,
Jing Li,
Jiangnan Dai,
Xiang Ma,
Hanling Long,
Yi Zhang,
Qiaoyin Lu,
John F. Donegan,
Weihua Guo
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.395013
Subject(s) - octave (electronics) , materials science , supercontinuum , optics , frequency comb , optoelectronics , sapphire , photolithography , nonlinear optics , pockels effect , second harmonic generation , laser , wavelength , physics , photonic crystal fiber
Single-crystal aluminum nitride (AlN) possessing both strong Pockels and Kerr nonlinear optical effects as well as a very large band gap is a fascinating optical platform for integrated nonlinear optics. In this work, fully etched AlN-on-sapphire microresonators with a high-Q of 2.1 × 10 6 for the TE 00 mode are firstly demonstrated with the standard photolithography technique. A near octave-spanning Kerr frequency comb ranging from 1100 to 2150 nm is generated at an on-chip power of 406 mW for the TM 00 mode. Due to the high confinement, the TE 10 mode also excites a Kerr comb from 1270 to 1850nm at 316 mW. In addition, frequency conversion to visible light is observed during the frequency comb generation. Our work will lead to a large-scale, low-cost, integrated nonlinear platform based on AlN.