Mechanically actuated Kerr soliton microcombs

Mode-locked ultrashort pulse sources with a repetition rate of up to several tens of gigahertz greatly facilitate versatile photonic applications such as frequency synthesis, metrology, radar, and optical communications. Dissipative Kerr soliton microcombs provide an attractive solution as a broadband, high-repetition-rate compact laser system in this context. However, its operation usually requires sophisticated pump laser control to initiate and stabilize the soliton microcombs, particularly in millimeter-sized ultrahigh-Q whispering-gallery resonators. Here, we realize a mechanically actuated soliton microcomb oscillator with a microwave repetition rate of 15 GHz. This enables direct soliton initiation, long-term stabilization, and fine tuning, where the operation now lifts the prerequisite pump laser tunability that must be relaxed if the technology is to be widely used outside the laboratory environment. We reveal the prospects for using this method with a wide range of applications that would benefit from mechanical soliton actuation such as optical clocks, spectral extension, and dual-comb spectroscopy

Integrated microresonator frequency comb source for massive-parallel optical communication

We demonstrated ultra-dense wavelength-division multiplexing (WDM) data transmission using an intensity modulation and direct detection (IM-DD) scheme. We discuss the feasibility of SiN and MgF2 microresonators for WDM applications regarding output power, bandwidth, and required pumping power. In addition, we discuss that IM-DD communication is relevant to the next-generation optical communication that requires ultra-low latency

Versatile tuning of Kerr soliton microcombs in crystalline microresonators

High-repetition rate microresonator-based frequency combs offer powerful and compact optical frequency comb sources that are of great importance to various applications. Here, the authors extend the tunability of the Kerr soliton frequency combs by exploiting thermal effects and frequency stabilization techniques