Demonstration of optical multicasting using Kerr frequency comb lines

We experimentally demonstrate optical multicasting using Kerr frequency combs generated from a Si3N4 microresonator. We obtain Kerr combs in two states with different noise properties by varying the pump wavelength in the resonator and investigate the effect of Kerr combs on multicasting. Seven-fold multicasting of 20 Gbaud quadrature phase-shift-keyed signals and four-fold multicasting of 16-quadrature amplitude modulation signals have been achieved when low-phase-noise combs are input into a periodically poled lithium niobate waveguide. In addition, we find that the wavelength conversion efficiency in the PPLN waveguide for chaotic combs with high noise is similar to that for low-noise combs, while the signal quality of the multicast copy is significantly degraded. (C) 2016 Optical Society of America

Dependence of a microresonator Kerr frequency comb on the pump linewidth

Maxim Karpov, Tobias Kippenberg, Arne Kordts, Amirhossein Mohajerin Ariaei, Martin Hubert Peter Pfeiffer, Lin Zhang

We experimentally investigate the dependence of Kerr comb generation, comb linewidth, and coherent system performance on the pump linewidth in a microresonator. We find that the generation of the primary comb can have a larger tolerance to the pump linewidth compared with that of the low-phase-noise comb. In addition, the linewidths of the generated combs are almost linearly dependent on the pump linewidth in the primary and low-phase-noise states. Furthermore, the optical signal-to-noise ratio penalty between the pump and generated Kerr combs in a coherent communication systemis less than 0.2 dB in both the primary and low-phase-noise states, showing that Kerr frequency combs in these two states can have similar coherent system performance to the pump. (C) 2017 Optical Society of America

Optical Society of America2017

Octave-spanning dissipative Kerr soliton frequency combs in Si3N4 microresonators

Hairun Guo, Clemens Herkommer, Maxim Karpov, Tobias Kippenberg, Junqiu Liu, Erwan Guillaume Albert Lucas, Martin Hubert Peter Pfeiffer, Michail Zervas

Octave-spanning, self-referenced frequency combs are applied in diverse fields ranging from precision metrology to astrophysical spectrometer calibration. The octave-spanning optical bandwidth is typically generated through non-linear spectral broadening of femtosecond pulsed lasers. In the past decade, Kerr frequency comb generators emerged as a novel scheme offering chip-scale integration, high repetition rate, and bandwidths that are only limited by group velocity dispersion. The recent observation of the dissipative Kerr soliton (DKS) operation regime, along with dispersive wave formation, has provided the means for fully coherent, broadband Kerr frequency comb generation with an engineered spectral envelope. Here, by carefully optimizing the photonic Damascene fabrication process, and dispersion engineering of Si3N4 microresonators with a free spectral range of 1 THz, we achieve bandwidths exceeding one octave at low powers (similar to 100 mW) for pump lasers residing in the telecom C band (1.55 mu m) as well as in the O band (1.3 mu m). Precise dispersion engineering enables emission of two dispersive waves, increasing the power in the spectral ends of the comb, down to a wavelength as short as 850 nm. Investigating the coherence of the generated Kerr comb states, we unambiguously identify DKS states using a response measurement. This allows demonstrating octave-spanning DKS comb states at both pump laser wavelengths of 1.3 mu m and 1.55 mu m, including the broadest DKS state generated to date, spanning more than 200 THz of optical bandwidth. Octave-spanning DKS frequency combs can be applied in metrology or spectroscopy, and their operation at 1.3 mu m enables applications in biological and medical imaging such as Kerr-comb-based optical coherence tomography or dual-comb coherent anti-Stokes Raman scattering. (C) 2017 Optical Society of America

Optical Soc Amer2017

Octave-spanning dissipative Kerr soliton frequency combs in Si3N4 microresonators

Hairun Guo, Clemens Herkommer, Maxim Karpov, Tobias Kippenberg, Junqiu Liu, Erwan Guillaume Albert Lucas, Martin Hubert Peter Pfeiffer, Michail Zervas

Optical Soc Amer2017