Infrared Laser Locking to Rubidium Saturated Absorption Spectrum via a Photonic Chip Frequency Doubler

Abstract

Photonic integrated resonators stand out as reliable frequency converters due to their compactness and stability, with second-harmonic generation (SHG) efficiencies of up to 17000%/W reported recently in aluminum nitride microrings. In this work, a sufficiently strong second-harmonic (SH) signal up to microwatts was generated by a photonic integrated frequency doubler using a milliwatt infrared (IR) laser source. Furthermore, increased SHG bandwidth covering ${}^{85}$Rb and ${}^{87}$Rb D${}_2$ transition lines as well as saturated absorption spectroscopy (SAS) were demonstrated by tuning the pump power and chip temperature. Here, we present, to the best of our knowledge, the first successful locking of an IR laser to Rb saturated absorption lines via a photonic chip frequency doubler.

arXiv comment4 pages, 4 figures

References in corpus (5)

• Ultrahigh-efficiency second-harmonic generation in nanophotonic PPLN waveguides
• 17,000 %/W Second Harmonic Conversion Efficiency in Single Crystalline Aluminum Nitride Microresonators
• Efficient visible frequency comb generation via Cherenkov radiation from a Kerr microcomb
• 400%/W second harmonic conversion efficiency in $14\mu \mathrm{m}$-diameter gallium phosphide-on-oxide resonators
• Photonic integration of an optical atomic clock

Cited by in corpus (3)

• Efficient frequency conversion in a degenerate ${\chi }^{(2)}$ microresonator
• Nonlinear optical radiation of a lithium niobate microcavity
• Miniaturized saturated absorption spectrometer