{ "id": "1908.06643", "version": "v1", "published": "2019-08-19T08:41:59.000Z", "updated": "2019-08-19T08:41:59.000Z", "title": "Taming two interacting particles with disorder", "authors": [ "Diana Thongjaomayum", "Alexei Andreanov", "Thomas Engl", "Sergej Flach" ], "comment": "4 pages, 4 figures", "categories": [ "cond-mat.dis-nn" ], "abstract": "We compute the scaling properties of the localization length $\\xi_2$ of two interacting particles in a one-dimensional chain with diagonal disorder, and the connectivity properties of the Fock states. We analyze record large system sizes (up to $N=20000$) and disorder strengths (down to $W=0.5$). We vary the energy $E$ and the on-site interaction strength $u$. At a given disorder strength the largest enhancement of $\\xi_2$ occurs for $u$ of the order of the single particle band width, and for two-particle states with energies at the center of the spectrum, $E=0$. We observe a crossover in the scaling of $\\xi_2$ with the single particle localization length $\\xi_1$ into the asymptotic regime for $\\xi_1 > 100$ ($W < 1.0$). This happens due to the recovery of translational invariance and momentum conservation rules in the matrix elements of interconnected Fock eigenstates for $u=0$. The entrance into the asymptotic scaling is manifested through a nonlinear scaling function $\\xi_2/\\xi_1=F(u\\xi_1)$.", "revisions": [ { "version": "v1", "updated": "2019-08-19T08:41:59.000Z" } ], "analyses": { "keywords": [ "interacting particles", "analyze record large system sizes", "disorder strength", "single particle band width", "single particle localization length" ], "note": { "typesetting": "TeX", "pages": 4, "language": "en", "license": "arXiv", "status": "editable" } } }