Spectral line-by-line pulse shaping of on-chip microresonator frequency combs

Fahmida Ferdous, Purdue University
Houxun Miao, National Institute of Standards & Technology, University of Maryland - College Park
Daniel E. Leaird, Purdue University - Main Campus
Kartik Srinivasan, National Institute of Standards & Technology
Jian Wang, Birck Nanotechnology Center, Purdue University
Lei Chen, National Institute of Standards & Technology
Leo Tom Varghese, Birck Nanotechnology Center, Purdue University
Andrew M. Weiner, Birck Nanotechnology Center, Purdue University

Date of this Version



Nature Photonics 5, 770–776 (2011)


Recently, on-chip comb generation methods based on nonlinear optical modulation in ultrahigh-quality-factor monolithic microresonators have been demonstrated, where two pump photons are transformed into sideband photons in a four-wave-mixing process mediated by Kerr nonlinearity. Here, we investigate line-by-line pulse shaping of such combs generated in silicon nitride ring resonators. We observe two distinct paths to comb formation that exhibit strikingly different time-domain behaviours. For combs formed as a cascade of sidebands spaced by a single free spectral range that spread from the pump, we are able to compress stably to nearly bandwidth-limited pulses. This indicates high coherence across the spectra and provides new data on the high passive stability of the spectral phase. For combs where the initial sidebands are spaced by multiple free spectral ranges that then fill in to give combs with single free-spectral-range spacing, the time-domain data reveal partially coherent behaviour.


Nanoscience and Nanotechnology