Clemens Herkommer

Mid-infrared frequency comb via coherent dispersive wave generation in silicon nitride nanophotonic waveguides

Clemens Herkommer, 2, ∗ Adrien Billat, ∗ Hairun Guo, ∗ Davide Grassani, Chuankun Zhang, 4 Martin H. P. Pfeiffer, Camille-Sophie Brès, † and Tobias J. Kippenberg ‡ École Polytechnique Fédérale de Lausanne (EPFL), LPQM, CH-1015 Lausanne, Switzerland Technische Universität München (TUM), Physik-Department, D-80333 München, Germany École Polytechnique Fédérale de Lausanne (EPFL), PHOSL, CH-1015 Lausanne, Switzerland Tsinghua University, Beijing 100084, China

A chip-based silicon nitride platform for mid-infrared nonlinear photonics

We developed a chip-based silicon nitride platform with thick waveguides (> 2 μm) that overcomes the usual fabrication limitation. We demonstrate both microresonator frequency comb generation at 2.5 μm and supercontinuum generation extending beyond 4.0 μm in this platform.

Soliton Kerr frequency combs with octave bandwidth in integrated Si 3 N 4 microresonators

Frequency combs provide a set of equidistant laser lines and find applications in many areas [1]. Microresonator based Kerr frequency combs are a recent scheme for frequency comb generation promising chip-level integration and novel applications such as coherent terabit telecommunications [2, 3]. The underlying principle is nonlinear frequency conversion of a continuous wave pump laser in a high finesse microresonator. Recently the excitation of dissipative Kerr solitons (DKS) and dispersive wave (DW) formation within the resonator has provided a path to fully coherent Kerr frequency combs with engineered bandwidth [4, 5]. Attaining spectral coverage exceeding one octave is key for several applications like self-referencing via f-2f-interferometry. Although octave spanning Kerr combs have been reported, exciting fully coherent DKS based frequency combs with octave bandwidth has remained challenging.