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Theory of Electron Density of States of High Temperature Impurity Induced Anharmonic Superconductors

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DOI: 10.4236/ampc.2012.24037    3,624 Downloads   5,716 Views  

ABSTRACT

The expression for the electron density of states (EDOS) of high temperature superconductors (HTS) has been derived taking the disorder and anharmonicity effects as a central problem. This has been dealt with the help of double time thermodynamic Green’s function theory for electrons via a generalized Hamiltonian which consists of the contribution due to 1) unperturbed electrons; 2) unperturbed phonons; 3) isotopic impurities; 4) anharmonicities (no BCS type Hamiltonian has been taken up in the formulation); and 5) electron-phonon interactions. The renormalization effects and emergence of pairons appears as a unique feature of the theory and dependence of EDOS on impurity concentration and temperature has been discussed in details with special reference to the HTS.

Conflicts of Interest

The authors declare no conflicts of interest.

Cite this paper

H. Singh, A. Singh, V. Ashokan and B. Indu, "Theory of Electron Density of States of High Temperature Impurity Induced Anharmonic Superconductors," Advances in Materials Physics and Chemistry, Vol. 2 No. 4, 2012, pp. 249-254. doi: 10.4236/ampc.2012.24037.

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