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Abstract The invention of the laser unleashed the potential of optical metrology, leading to numerous advancements in modern science and technology. This reliance on lasers, however, also introduces a bottleneck for precision optical metrology, as it requires sophisticated photonic infrastructure for precise laser-wave control, leading to limited metrology performance and significant system complexity. Here, we take a key step toward overcoming this challenge by demonstrating a Pockels laser with multifunctional capabilities that elevate optical metrology to a new level. The chip-scale laser achieves a narrow intrinsic linewidth down to 167 Hz and a broad mode-hop-free tuning range up to 24 GHz. In particular, it delivers an unprecedented frequency chirping rate of up to 20 EHz/s and an exceptional modulation bandwidth exceeding 10 GHz, both of which are orders of magnitude greater than those of existing lasers. Leveraging this laser, we successfully achieve velocimetry at 40 m/s over a short distance of 0.4 m, and measurable velocities up to the first cosmic velocity at 1 m away—a feat unattainable with conventional ranging approaches. At the same time, we achieve distance metrology with a ranging resolution of <2 cm. Furthermore, for the first time to our knowledge, we implement a dramatically simplified architecture for laser frequency stabilization by directly locking the laser to an external reference gas cell without requiring additional external light control. This approach enables long-term laser stability with a frequency fluctuation of only ±6.5 MHz over 60 min. The demonstrated Pockels laser combines elegantly high laser coherence with ultrafast frequency reconfigurability and superior multifunctional capability. We envision its profound impact across diverse fields including communication, sensing, autonomous driving, quantum information processing, and beyond. 

Temporal soliton mode locking in coherently pumped microcavities is a promising route towards miniaturized frequency comb systems. However, the power efficiency of the resulting microcombs is usually quite low. Soliton generation by pulse pumping provides a way to increase conversion efficiency (so far, as high as 8%). Here, we study conversion efficiency and report a single-soliton conversion efficiency as high as 54% using a scanning laser, as well as a steady-state single-soliton conversion efficiency as high as 34%. We use the Lagrangian approach to develop analytical expressions for efficiency and soliton temporal placement within the pumping pulse, and our measurements reveal features in the tuning dependence of soliton power and efficiency not seen in continuous pumping. Our experimentally confirmed expressions for efficiency will be useful in understanding advantages and limitations of pulse pumped systems. 

Abstract Since its invention, optical frequency comb has revolutionized a broad range of subjects from metrology to spectroscopy. The recent development of microresonator-based frequency combs (microcombs) provides a unique pathway to create frequency comb systems on a chip. Indeed, microcomb-based spectroscopy, ranging, optical synthesizer, telecommunications and astronomical calibrations have been reported recently. Critical to many of the integrated comb systems is the broad coverage of comb spectra. Here, microcombs of more than two-octave span (450 nm to 2,008 nm) is demonstrated throughχ⁽²⁾andχ⁽³⁾nonlinearities in a deformed silica microcavity. The deformation lifts the circular symmetry and creates chaotic tunneling channels that enable broadband collection of intracavity emission with a single waveguide. Our demonstration introduces a new degree of freedom, cavity deformation, to the microcomb studies, and our microcomb spectral range is useful for applications in optical clock, astronomical calibration and biological imaging. 

Abstract High‐coherence visible and near‐visible laser sources are centrally important to the operation of advanced position/navigation/timing systems as well as classical/quantum sensing systems. However, the complexity and size of these bench‐top lasers are an impediment to their transition beyond the laboratory. Here, a system‐on‐chip that emits high‐coherence near‐visible lightwaves is demonstrated. The devices rely upon a new approach wherein wavelength conversion and coherence increase by self‐injection locking are combined within a single nonlinear resonator. This simplified approach is demonstrated in a hybridly‐integrated device and provides a short‐term linewidth of around 4.7 kHz (10 kHz before filtering). On‐chip converted optical power over 2 mW is also obtained. Moreover, measurements show that heterogeneous integration can result in a conversion efficiency higher than 25% with an output power over 11 mW. Because the approach uses mature III–V pump lasers in combination with thin‐film lithium niobate, it can be scaled for low‐cost manufacturing of high‐coherence visible emitters. Also, the coherence generation process can be transferred to other frequency conversion processes, including optical parametric oscillation, sum/difference frequency generation, and third‐harmonic generation.