{ "id": "2107.06364", "version": "v1", "published": "2021-07-13T20:00:30.000Z", "updated": "2021-07-13T20:00:30.000Z", "title": "Scaling Theory of Few-Particle Delocalization", "authors": [ "Louk Rademaker" ], "comment": "9 pages, 2 figures", "categories": [ "cond-mat.dis-nn", "cond-mat.quant-gas", "cond-mat.str-el" ], "abstract": "We develop a scaling theory of interaction-induced delocalization of few-particle states in disordered quantum systems. In the absence of interactions, all single-particle states are localized in $d<3$, while in $d \\geq 3$ there is a critical disorder below which states are delocalized. We hypothesize that such a delocalization transition occurs for $n$-particle bound states in $d$ dimensions when $d+n\\geq 4$. Exact calculations of disorder-averaged $n$-particle Greens functions support our hypothesis. In particular, we show that $3$-particle states in $d=1$ with nearest-neighbor repulsion will delocalize with $W_c \\approx 1.4t$ and with localization length critical exponent $\\nu = 1.5 \\pm 0.3$. The delocalization transition can be understood by means of a mapping onto a non-interacting problem with symplectic symmetry. We discuss the importance of this result for many-body delocalization, and how few-body delocalization can be probed in cold atom experiments.", "revisions": [ { "version": "v1", "updated": "2021-07-13T20:00:30.000Z" } ], "analyses": { "keywords": [ "scaling theory", "few-particle delocalization", "particle greens functions support", "particle bound states", "delocalization transition occurs" ], "note": { "typesetting": "TeX", "pages": 9, "language": "en", "license": "arXiv", "status": "editable" } } }