{"paper":{"title":"Anomalous behavior of the spin gap of a spin-1/2 two-leg antiferromagnetic ladder with Ising-like rung interactions","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cond-mat.stat-mech"],"primary_cat":"cond-mat.str-el","authors_text":"Kiyomi Okamoto, Shunsuke C. Furuya, Takashi Tonegawa, Toru Sakai","submitted_at":"2012-11-25T13:47:26Z","abstract_excerpt":"Using mainly numerical methods, we investigate the width of the spin gap of a spin-1/2 two-leg ladder described by $\\cH= J_\\rl \\sum_{j=1}^{N/2} [ \\vS_{j,a} \\cdot \\vS_{j+1,a} + \\vS_{j,b} \\cdot \\vS_{j+1,b} ] + J_\\rr \\sum_{j=1}^{N/2} [\\lambda (S^x_{j,a} S^x_{j,b} + S^y_{j,a} S^y_{j,b}) + S^z_{j,a} S^z_{j,b}] $, where $S^\\alpha_{j,a(b)}$ denotes the $\\alpha$-component of the spin-1/2 operator at the $j$-th site of the $a (b)$ chain. We mainly focus on the $J_\\rr \\gg J_\\rl > 0$ and $|\\lambda| \\ll 1$ case. The width of the spin gap as a function of $\\lambda$ anomalously increases near $\\lambda = 0$;"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1211.5764","kind":"arxiv","version":2},"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"}