We demonstrate high-quality(intrinsic Q factor∼2.8×106)racetrack microresonators fabricated on lithium niobate thin film with a free spectral range(FSR)of∼86 pm.By integrating microelectrodes alongside the two ...We demonstrate high-quality(intrinsic Q factor∼2.8×106)racetrack microresonators fabricated on lithium niobate thin film with a free spectral range(FSR)of∼86 pm.By integrating microelectrodes alongside the two straight arms of the racetrack resonator,the resonance wavelength around 1550 nm can be red shifted by 92 pm when the electric voltage is raised from−100 V to 100 V.The microresonators with the tuning range spanning over a full FSR are fabricated using photolithography assisted chemo-mechanical etching.展开更多
Dispersion engineering of optical waveguides is among the most important steps in enabling the realization of Kerr optical frequency combs.A recurring problem is the limited bandwidth in which the nonlinear phase matc...Dispersion engineering of optical waveguides is among the most important steps in enabling the realization of Kerr optical frequency combs.A recurring problem is the limited bandwidth in which the nonlinear phase matching condition is satisfied,due to the dispersion of the waveguide.This limitation is particularly stringent in high-index-contrast technologies such as silicon-on-insulator.We propose a general approach to stretch the bandwidth of Kerr frequency combs based on subwavelength engineering of single-mode waveguides with self-adaptive boundaries.The wideband flattened dispersion operation comes from the particular property of the waveguide optical mode that automatically self-adapts its spatial profile at different wavelengths to slightly different effective spatial spans determined by its effective index values.This flattened dispersion relies on the squeezing of small normal-dispersion regions between two anomalous spectral zones,which enables it to achieve two Cherenkov radiation points and substantially broaden the comb,achieving a bandwidth between 2.2 and 3.4μm wavelength.This strategy opens up a design space for trimming the spectra of Kerr frequency combs using high-index-contrast platforms and can provide benefits to various nonlinear applications in which the manipulation of energy spacing and phase matching are pivotal.展开更多
基金funded by the National Key R&D Program of China(No.2019YFA0705000)the National Natural Science Foundation of China(Nos.12004116,11874154,and 11734009)+2 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB16030300)the Shanghai Municipal Science and Technology Major Project(No.2019SHZDZX01)the Natural Science and Engineering Research Council of Canada(NSERC)Discovery(No.RGPIN-2020-05938)。
文摘We demonstrate high-quality(intrinsic Q factor∼2.8×106)racetrack microresonators fabricated on lithium niobate thin film with a free spectral range(FSR)of∼86 pm.By integrating microelectrodes alongside the two straight arms of the racetrack resonator,the resonance wavelength around 1550 nm can be red shifted by 92 pm when the electric voltage is raised from−100 V to 100 V.The microresonators with the tuning range spanning over a full FSR are fabricated using photolithography assisted chemo-mechanical etching.
基金the French national research agency(BRIGHT ANR project)
文摘Dispersion engineering of optical waveguides is among the most important steps in enabling the realization of Kerr optical frequency combs.A recurring problem is the limited bandwidth in which the nonlinear phase matching condition is satisfied,due to the dispersion of the waveguide.This limitation is particularly stringent in high-index-contrast technologies such as silicon-on-insulator.We propose a general approach to stretch the bandwidth of Kerr frequency combs based on subwavelength engineering of single-mode waveguides with self-adaptive boundaries.The wideband flattened dispersion operation comes from the particular property of the waveguide optical mode that automatically self-adapts its spatial profile at different wavelengths to slightly different effective spatial spans determined by its effective index values.This flattened dispersion relies on the squeezing of small normal-dispersion regions between two anomalous spectral zones,which enables it to achieve two Cherenkov radiation points and substantially broaden the comb,achieving a bandwidth between 2.2 and 3.4μm wavelength.This strategy opens up a design space for trimming the spectra of Kerr frequency combs using high-index-contrast platforms and can provide benefits to various nonlinear applications in which the manipulation of energy spacing and phase matching are pivotal.
