Ultra-High Q Silicon Nitride Microresonators Enabled Raman Lasing

Silicon nitride (Si<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>N<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</inf>), among other materials, is particularly attractive for linear and nonlinear optics because of its ultra-low loss properties, enabling advances in various fields, including narrow linewidth lasers [1], Kerr frequency comb [2], quantum photonics [3], etc. One of the important examples is stimulated Raman scattering. It is an efficient approach to extend the available spectral coverage of conventional laser sources [4], [5], enabling applications including molecular spectroscopy, environmental analysis, and biological detection [6]. Intrapulse Raman scattering is broadband in nature in amorphous materials such as silica and Si<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>N<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</inf>, which relates to the vibrational material response of the cubic nonlinearity. This work presents the on-chip continuous-wave (CW) Raman laser generation in Si<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>N<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</inf> platform, which is benefited from the enhanced intracavity power of ultra-high quality factor (Q) microresonators.