Deriving the electron-phonon spectral density of MgB2 from optical data, using maximum entropy techniques.
We use maximum entropy techniques to extract an electron-phonon density from optical data for the normal state at T = 45 K of MgB2. Limiting the analysis to a range of phonon energies below 110 meV, which is sufficient for capturing all phonon structures, we find a spectral function that is in good agreement with that calculated for the quasi-two-dimensional σ-band. Extending the analysis to higher energies, up to 160 meV, we find no evidence for any additional contributions to the fluctuation spectrum, but find that the data can only be understood if the density of states is taken to decrease with increasing energy.
Department of Physics, Sungkyunkwan University, Suwon, Gyeonggi-do 440-746, Korea.
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J
Hwang
J P
JP
Carbotte