Author Correction: Electrically pumped photonic integrated soliton microcomb.

The original version of this Article contained an error in the first sentence of the Acknowledgements, which incorrectly read 'This publication was supported by Contract HR0011-15-C-0055 (DODOS) from the Defense Advanced Research Projects Agency (DARPA), Defense Sciences Office (DSO).' The correct version states 'Microsystems Technology Office (MTO)' in place of 'Defense Sciences Office (DSO)'. This has been corrected in both the PDF and HTML versions of the Article.

Electrically pumped photonic integrated soliton microcomb.

Microcombs provide a path to broad-bandwidth integrated frequency combs with low power consumption, which are compatible with wafer-scale fabrication. Yet, electrically-driven, photonic chip-based microcombs are inhibited by the required high threshold power and the frequency agility of the laser for soliton initiation. Here we demonstrate an electrically-driven soliton microcomb by coupling a III-V-material-based (indium phosphide) multiple-longitudinal-mode laser diode chip to a high-Q silicon nitride microresonator fabricated using the photonic Damascene process. The laser diode is self-injection locked to the microresonator, which is accompanied by the narrowing of the laser linewidth, and the simultaneous formation of dissipative Kerr solitons. By tuning the laser diode current, we observe transitions from modulation instability, breather solitons, to single-soliton states. The system operating at an electronically-detectable sub-100-GHz mode spacing requires less than 1 Watt of electrical power, can fit in a volume of ca. 1 cm3, and does not require on-chip filters and heaters, thus simplifying the integrated microcomb.

A novel approach to left atrial appendage exclusion: the WATCHMAN device.

Atrial fibrillation (AF), a very common cardiac arrhythmia, is a well-recognized predisposing factor for embolic stroke. While warfarin remains the cornerstone of anticoagulant treatment in patients with AF, it is often underutilized because of increased bleeding complications and frequent monitoring requirements. It has been documented that the left atrial appendage (LAA) is the main source of left atrial thrombus that causes strokes in AF patients. Thus, closure of the LAA may be an effective strategy in stroke reduction. Several devices have been used in closure of the LAA. The WATCHMAN device appears to be a safe and efficacious device for closure of the LAA as recently demonstrated in the PROTECT AF trial.