d-wave superconductivity from electron-phonon interactions
نویسنده
چکیده
I examine electron-phonon mediated superconductivity in the intermediate coupling and phonon frequency regime of the quasi-2D Holstein model. I use an extended Migdal–Eliashberg theory which includes vertex corrections and spatial fluctuations. I find a d-wave superconducting state that is unique close to half-filling. The order parameter undergoes a transition to s-wave superconductivity on increasing filling. I explain how the inclusion of both vertex corrections and spatial fluctuations is essential for the prediction of a d-wave order parameter. I then discuss the effects of a large Coulomb pseudopotential on the superconductivity (such as is found in contemporary superconducting materials like the cuprates), which results in the destruction of the s-wave states, while leaving the d-wave states unmodified. Published as: Phys. Rev. B 73, 060503(R) (2006)
منابع مشابه
d-wave superconductivity from electron-phonon interactions
The Open University's repository of research publications and other research outputs d-wave superconductivity from electron-phonon interactions Journal Article How to cite: Hague, J. P. (2006). d-wave superconductivity from electron-phonon interactions. Physical Review B, 73(6) 060503. For guidance on citations see FAQs. c [not recorded] Version: [not recorded] Link(s) to article on publisher's...
متن کاملd-wave superconductivity from electron-phonon interactions
The Open University's repository of research publications and other research outputs d-wave superconductivity from electron-phonon interactions Journal Article How to cite: Hague, J. P. (2006). d-wave superconductivity from electron-phonon interactions. Physical Review B, 73(6) 060503. For guidance on citations see FAQs. c [not recorded] Version: [not recorded] Link(s) to article on publisher's...
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