Question

51. There is a class of electronic impurity centers in crystals called "color centers." The absorption coeff- cient produced by one such center, the "F center in a sodium chloride crystal, is shown in Fig. 2.30.Treat this center as a harmonic oscillator with the mass of an electron imbedded in the crystal (of refractive index n 1.55). Assume the experimental lineshape to be Lorentzian, and from it estimate the lifetime of the oscillator and the oscillator strength. Calculate a value for the maximum change in the real part of the index of refraction caused by the presence of the F centers in this sample. 5 a 10 5 6 7 8× 1014/sec Frequency v Fig. 2.30

Answer 1

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Pege-2. sobstitufing The values otns !. 5s s given 27 -15 Similar esrom the graph and using te above value of τ inte secod ution we neol The re ccoi tten Tue maximum konge of sepoactive irdex an be peodb s Scaned with CamScanner