The Drude-Lorentz formula for the dielectric constant (e(w)) of a solid is: e(w) = 1 +...

 

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The Drude-Lorentz formula for the dielectric constant (e(w)) of a solid is: e(w) = 1 + (w²w²) - it-tw where the plasma frequency w is given by (ne2)/(com), with charge e, electron mass m, to the vacuum permittivity and the concentration of free electrons n = 8.4 x 1028 m-3, 7 is the scattering time of the electrons and the resonant frequency wo is proportional to the energy gap for the intraband transition. i. Assume in a sample of copper the colour corresponds to a wavelength of 6x107 m. Calculate wp and wo in eV. [3] ii. Calculate expressions for, and sketch the real and imaginary part of e(w) as a function of w. [7] The Drude-Lorentz formula for the dielectric constant (e(w)) of a solid is: e(w) = 1 + (w²w²) - it-tw where the plasma frequency w is given by (ne2)/(com), with charge e, electron mass m, to the vacuum permittivity and the concentration of free electrons n = 8.4 x 1028 m-3, 7 is the scattering time of the electrons and the resonant frequency wo is proportional to the energy gap for the intraband transition. i. Assume in a sample of copper the colour corresponds to a wavelength of 6x107 m. Calculate wp and wo in eV. [3] ii. Calculate expressions for, and sketch the real and imaginary part of e(w) as a function of w. [7]

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i To calculate the plasma frequency wp in ev we can use the equation wp ne2epsilon0m where n is the ... View the full answer