Superconductivity with and without glue and the role of the double-occupancy forbidding constraint in the t-J-V model
The occurrence of retarded (with glue) and unretarded (without glue) pairing is thoroughly discussed in cuprates. We analyze some aspects of this problem in the context of the t − J − V model in a large- N approximation. When 1 / N renormalizations are neglected the mean-field result is recovered, w...
| Autores: | , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2021 |
| País: | Argentina |
| Institución: | Consejo Nacional de Investigaciones Científicas y Técnicas |
| Repositorio: | CONICET Digital (CONICET) |
| Idioma: | inglés |
| OAI Identifier: | oai:ri.conicet.gov.ar:11336/183066 |
| Acceso en línea: | http://hdl.handle.net/11336/183066 |
| Access Level: | acceso abierto |
| Palabra clave: | SUPERCONDUCTIVITY CUPRATES T-J MODEL https://purl.org/becyt/ford/1.3 https://purl.org/becyt/ford/1 |
| Sumario: | The occurrence of retarded (with glue) and unretarded (without glue) pairing is thoroughly discussed in cuprates. We analyze some aspects of this problem in the context of the t − J − V model in a large- N approximation. When 1 / N renormalizations are neglected the mean-field result is recovered, where the unretarded d -wave superconducting pairing triggered by the spin-exchange interaction J is obtained. However, the presence of a nonnegligible nearest-neighbors Coulomb interaction V ( q ) kills superconductivity. If the non-double-occupancy constraint and its fluctuations are considered, the situation changes drastically. In this case, V ( q ) is screened making d -wave superconductivity very robust. In addition, we show that the early proposal for the presence of an unretarded pairing contribution triggered by the spin-exchange interaction J can be discussed in this context. |
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