Beyond 100 THz-spanning ultraviolet frequency combs in a non-centrosymmetric crystalline waveguide

Abstract

Ultraviolet frequency combs enable applications ranging from precision spectroscopy to atomic clocks by addressing the electronic transitions of atoms and molecules. Access to ultraviolet light via integrated nonlinear optics is usually hampered by the strong material dispersion and large waveguide attention in the ultraviolet region. Here we demonstrate a simple route to chip-scale ultraviolet comb generators, simultaneously showing a gap-free frequency span of ~128 terahertz and supercontinuum sourced by an ultrafast fiber laser. The simultaneous cubic and quadratic nonlinear processes are implemented in single-crystalline aluminum nitride thin films, where a chirp-modulated taper waveguide is patterned to ensure a broad phase matching. The heterodyne beatnote characterization suggests that both the near-visible and ultraviolet supercontinuum combs maintain a high degree of coherence. Our approach is also adaptable to other non-centrosymmetric photonic platforms for ultrafast nonlinear optics with scalable bandwidth.

arXiv comment9 pages, 4 figures

References in corpus (13)

• An atomic clock with $10^{-18}$ instability
• Ultrahigh-efficiency second-harmonic generation in nanophotonic PPLN waveguides
• Mid-infrared frequency comb generation with silicon nitride nano-photonic waveguides
• Integrated optical addressing of an ion qubit
• Geometrical Representation of Sum Frequency Generation and Adiabatic Frequency Conversion
• 17,000 %/W Second Harmonic Conversion Efficiency in Single Crystalline Aluminum Nitride Microresonators
• Ultrabroadband supercontinuum generation and frequency-comb stabilization using on-chip waveguides with both cubic and quadratic nonlinearities
• Ultra-high-Q UV microring resonators based on single-crystalline AlN platform
• 400%/W second harmonic conversion efficiency in $14\mu \mathrm{m}$-diameter gallium phosphide-on-oxide resonators
• Quantum frequency conversion between infrared and ultraviolet
• Frequency comb up- and down-conversion in a synchronously-driven ${\chi }^{(2)}$ optical microresonator
• Quasi-phase-matched supercontinuum-generation in photonic waveguides
• Direct frequency comb spectroscopy of trapped ions

Cited by in corpus (10)

• III-Nitride nanophotonics for beyond-octave soliton generation and self-referencing
• Dissipative Kerr Solitons in a III-V Microresonator
• 2023 Astrophotonics Roadmap: pathways to realizing multi-functional integrated astrophotonic instruments
• Visible blue-to-red 10 GHz frequency comb via on-chip triple-sum frequency generation
• Ultraviolet astronomical spectrograph calibration with laser frequency combs from nanophotonic lithium niobate waveguides
• Supercontinuum generation assisted by dispersive waves trapping in dispersion-managed integrated silicon waveguides
• Ultrafast-nonlinear ultraviolet pulse modulation in an AlInGaN polariton waveguide operating up to room temperature
• Stable and compact RF-to-optical link using lithium niobate on insulator waveguides
• Supercontinua from integrated gallium nitride waveguides
• Novel solitary and periodic waves in quadratic-cubic non-centrosymmetric waveguides