Research Of Precision Spectroscopy And Atomic Filter At 420nm Wavelength For Isotope ⁸⁷Rb

The semiconductor laser, because of its simple structure, small size, high efficiency, easy tuning, has important value in the production and research. The development and improvement of laser technology makes spectroscopy has undergone tremendous changes.Based on the interaction of light with matter, nonlinearspectroscopyhas thusproduced.With high resolution spectroscopy, high detection sensitivity and high temporal resolution, nonlinear spectroscopy has wide application value. Atomic filter is based on atomic absorption, emission and optical devices of the physical processes inside energy conversion. With narrow bandwidth, high transmittance characteristics, atomic filter has been applied in the laser satellite communications, laser radar remote sensing and underwater optical communications.In this paper, we use 420nm wavelength external cavity semiconductor laser toobserved precision spectroscopy in various isotope 87Rb 420nm transition. In SaturatedAbsorptionSpectroscopy experiment, we have obtainedthe narrowest width 6MHz, it corresponds to 5S1/2F=2 to 6P3/2 F'= 2,3 transitions lines. At the same time, we observed the fluorescence signal,Doppler spectroscopy and polarization spectroscopy.During the study of the atomic filter, based on the traditional isotope 87RbFaraday anomalous dispersion optical filter, we use the saturated absorption effect, combined with the Faraday effect and circular dichroism to realizethe ultra-narrow linewidth filter at 87Rb420nm atomic transition. By studying the impact of the pumping light power,temperature and magnetic field strength,we obtained the linewidthwith only 9MHzof theultra-narrow linewidth filter at 87Rb420nm atomic transitions.And the maximum transmission rate is 2%. The ultra-narrow linewidth filter at 87Rb420nm transition has not been reported by now.Finallythis paper also points out the possibility of further increasing the transmittance.