{"paper":{"title":"Double fluctuations on the attractive Hubbard model: ladder approximation","license":"","headline":"","cross_cats":["cond-mat.supr-con"],"primary_cat":"cond-mat.str-el","authors_text":"J. J. Rodriguez, S. Schafroth","submitted_at":"1997-01-05T14:39:16Z","abstract_excerpt":"We explore, for the first time, the effect of double fluctuations on both the diagonal and off-diagonal self-energy. We use the T-Matrix equations below $T_c$, developed recently by the Z\\\"urich group (M.H. Pedersen et al) for the local pair attraction Hamiltonian. Here, we include as well the effect of fluctuations on the order parameter (beyond the BCS solution) up to second order in $U/t$. This is equivalent to approximating the effective interaction by $U$ in the off-diagonal self-energy. For $U/t = -6.0$, $T/t = 0.05$, $\\mu/t = - 5.5$ and $\\Delta/t = 1.5$, we find four peaks both for the "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"cond-mat/9701017","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}