| International Journal of Advanced Applied Physics Research (Volume 2 Issue 1) |
| Properties of the Coherence Length and Van Hove Singularity in High-Tc Superconductors |
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Pages 19-30
A. Bechlaghem
DOI: http://dx.doi.org/10.15379/2408-977X.2015.02.01.3
Published: 15 June 2015 |
| Abstract |
| High- superconductors are characterized by a short coherence length. From the quasi-2D structure of these compounds, we calculate the density of states, the Fermi velocity and the gap energy. From these parameters, we deduce a formula of the coherence length. We study the effect of the phonon-interaction, the effective mass of carriers and the Coulomb repulsion on the coherence length. We show that when the coupling constant is in the range 0.06 – 0.30 and the effective mass is between 2m0 and 6m0 (m0 is the free electron mass), the values obtained of the coherence length and the gap energy are in a good agreement with experimental results. |
| Keywords |
| Superconductivity, Density of states, Coherence length, Fermi velocity, Fermi energy, Gap energy, Van Hove singularity, Phonon-interaction, Effective mass, Coulomb repulsion. |
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