Hyperfine Studies of Lithium using Saturated Absorption by xww95991

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									 Hyperfine Studies of
    Lithium using
Saturated Absorption
    Spectroscopy
         Tory Carr

   Advisor: Dr. Alex Cronin
Hyperfine Structure of   6Li   &   7Li
                      Normal Setup




                         6
                         Li D1
Transmission Signal




                                 7     6
                                 Li D1+ Li D2
                                                7
                                                Li D2
                Theoretical Limit



            8


                              6 MHz

            6
Intensity




            4




            2




            0
                      Problem
   Doppler Broadening “smears out”
    resolution




                                  3 GHz
          Intensity
                      Normal Setup




                         6
                         Li D1
Transmission Signal




                                 7     6
                                 Li D1+ Li D2
                                                7
                                                Li D2
        Theory
        at 375 C
Saturated Absorption Setup
                                       New Spectrum


                               -3
                           30x10


                                                6
                                                                           FS
                               25                Li D1
Transmission signal (mW)




                               20


                               15                               HFS

                               10                                                   HFS
                                                            7     6
                                                            Li D1+ Li D2
                                   5    experimental data
                                                                                7
                                        theoretical model                       Li D2
Saturated Absorption Signal

     Transmission Signal




                           800MHz
                                Data collected
                                at 375 C
Light as seen from the atoms


                       Pump beam


     probe beam
                  v0
Population Difference
      Scan in frequency
+dv




  0




-dv
Theoretical Model
Isotope/ Transition Difference
Variation with Buffer Gas Pressure
Temperature variation
Temperature variation- diff sig
Maximum in difference signal


Maximum Signal When:
                   Conclusion
   Limiting Factors in resolution
    – Other broadening mechanisms
    – Residual Doppler broadening
   Improvements to setup
    – Improved alignment
    – Reduce laser linewidth
   Further experiments
    – Effects of polarization
    – Magnetic field effects

								
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