2012/08/23 by D. Yeaton-Massey, David Yeaton-Massey, Rana X. Adhikari +1 · 15 citations
Physics and Astronomy · #Advanced Fiber Laser Technologies #Advanced Frequency and Time Standards #Computer science #Laser #Noise (video) #Optics #Phase noise #Physics #Quantum optics and atomic interactions #Second-harmonic generation #Telecommunications #physics.optics
paper · pdf · open access · doi:10.1364/oe.20.021019
published in Optics Express 20(19), 21019 (Optica Publishing Group) · Submitted to Optics Express June 2012
arxiv created 2012/08/23 · openalex publication_date 2012/08/29 · arxiv updated 2013/07/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We report a bound on the relative frequency fluctuations in nonlinear second harmonic generation. A 1,064 nm Nd:YAG laser is used to read out the phase of a Mach-Zehnder interferometer while PPKTP, a nonlinear crystal, is placed in each arm to generate second harmonic light. By comparing the arm length difference of the Mach Zehnder as read out by the fundamental 1064 nm light, and its second harmonic at 532 nm, we can bound the excess frequency noise introduced in the harmonic generation process. We report an amplitude spectral density of frequency noise with total RMS frequency deviation of 3 mHz and a minimum value of 20 μHz/Hz½ over 250 seconds with a measurement bandwidth of 128 Hz, corresponding to an Allan deviation of 10⁻¹⁹ at 20 seconds.