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arXiv · cond-mat/0104291

Optical conductivity and penetration depth in MgB2

A. V. Pronin·A. Pimenov·A. Loidl·S. I. Krasnosvobodtsev
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Abstract

The complex conductivity of a MgB2 film has been investigated in the frequency range 4 cm^{-1}< nu < 30 cm^{-1} and for temperatures 2.7 K < T <300 K. The overall temperature dependence of both components of the complex conductivity is reminiscent of BCS-type behavior, although a detailed analysis reveals a number of discrepancies. No characteristic feature of the isotropic BCS gap temperature evolution is observed in the conductivity spectra in the superconducting state. A peak in the temperature dependence of the real part of the conductivity is detected for frequencies below 9 cm^{-1}. The superconducting penetration depth follows a T^2 behavior at low temperatures.

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A. V. Pronin, A. Pimenov, A. Loidl, S. I. Krasnosvobodtsev. 2001-04-17. Optical conductivity and penetration depth in MgB2. https://doi.org/10.1103/physrevlett.87.097003

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