We report accurate phase stabilization of an interlocking pair of Kerr-microresonator frequency combs. The two combs, one based on silicon nitride and one on silica, feature nearly harmonic repetition frequencies and can be generated with one laser. The silicon-nitride comb supports an ultrafast-laser regime with three-optical-cycle, 1-picosecond-period soliton pulses and a total dispersive-wave-enhanced bandwidth of 170 THz, while providing a stable phase-link between optical and microwave frequencies. We demonstrate nanofabrication control of the silicon-nitride comb’s carrier-envelope offset frequency and spectral profile. The phase-locked combs coherently reproduce their clock with a fractional precision of , a behavior we verified through 2 h of measurement to reach . Our work establishes Kerr combs as a viable technology for applications like optical-atomic timekeeping and optical synchronization.
We demonstrate a dynamic snap-through from a primary to a secondary statically inaccessible stable configuration in single crystal silicon, curved, doubly clamped micromechanical beam structures. The nanoscale motion of the fabricated bistable micromechanical devices was transduced using a high speed camera. Our experimental and theoretical results collectively show that the transition between the two stable states was solely achieved by a tailored time dependent electrostatic actuation. Fast imaging of the micromechanical motion allowed for direct visualization of dynamic trapping at the statically inaccessible state. These results further suggest that our direct dynamic actuation transcends prevalent limitations in controlling geometrically non-linear microstructures, and may have applications extending to multi-stable, topologically optimized micromechanical logic and non-volatile memory architectures.
Thermal fluctuations often impose both fundamental and practical measurement limits on high-performance sensors, motivating the development of techniques that bypass the limitations imposed by thermal noise outside cryogenic environments. Here, we theoretically propose and experimentally demonstrate a measurement method that reduces the effective transducer temperature and improves the measurement precision of a dynamic impulse response signal. Thermal noise–limited, integrated cavity optomechanical atomic force microscopy probes are used in a photothermal-induced resonance measurement to demonstrate an effective temperature reduction by a factor of ≈25, i.e., from room temperature down as low as ≈12 K, without cryogens. The method improves the experimental measurement precision and throughput by >2×, approaching the theoretical limit of ≈3.5× improvement for our experimental conditions. The general applicability of this method to dynamic measurements leveraging thermal noise–limited harmonic transducers will have a broad impact across a variety of measurement platforms and scientific fields.
A standard paradigm of localization microscopy involves extension from two to three dimensions by engineering information into emitter images, and approximation of errors resulting from the field dependence of optical aberrations. We invert this standard paradigm, introducing the concept of fully exploiting the latent information of intrinsic aberrations by comprehensive calibration of an ordinary microscope, enabling accurate localization of single emitters in three dimensions throughout an ultrawide and deep field. To complete the extraction of spatial information from microscale bodies ranging from imaging substrates to microsystem technologies, we introduce a synergistic concept of the rigid transformation of the positions of multiple emitters in three dimensions, improving precision, testing accuracy, and yielding measurements in six degrees of freedom. Our study illuminates the challenge of aberration effects in localization microscopy, redefines the challenge as an opportunity for accurate, precise, and complete localization, and elucidates the performance and reliability of a complex microelectromechanical system.