De‐correlation technique for separation of drude parameters from wavelength modulation spectroscopy data

Separation of bound‐ and free‐electron contributionsto the dielectric function is necessary for an accurate analysis of interband transitions. A technique for doing this separation which does not require low energy data is presented. The technique makes use of the fact that the functions which describe the contributions of each part are sufficiently uncorrelated, allowing the construction of a correlation function which uses the Drude effective mass and Drude relaxation time as adjustable parameters. The technique is shown to properly separate a test function and to yield reasonable results from experimental data.