{
"id": "1805.06443",
"version": "v1",
"published": "2018-05-16T17:50:57.000Z",
"updated": "2018-05-16T17:50:57.000Z",
"title": "Many-body multi-valuedness of particle-current variance in closed and open cold-atom systems",
"authors": [
"Mekena Metcalf",
"Chen-Yen Lai",
"Massimiliano Di Ventra",
"Chih-Chun Chien"
],
"comment": "Main text: 5 pages, 3 figures. Supplemental information: 5 pages, 9 figures",
"categories": [
"cond-mat.quant-gas",
"cond-mat.mes-hall",
"quant-ph"
],
"abstract": "The quantum variance of an observable is a fundamental quantity in quantum mechanics, and the variance provides additional information other than the average itself. By examining the relation between the particle-current variance $(\\delta J)^2$ and the average current $J$ in both closed and open interacting fermionic systems, we show the emergence of a multi-valued Lissajous curve between $\\delta J$ and $J$ due to interactions. As a closed system we considered the persistent current in a benzene-like lattice enclosing an effective magnetic flux and solved it by exact diagonalization. For the open system, the steady-state current flowing through a few lattice sites coupled to two particle reservoirs was investigated using a Lindblad equation. In both cases, interactions open a loop and change the topology of the corresponding $\\delta J$-$J$ Lissajous curve, showing that this effect is model-independent. We finally discuss how the predicted phenomena can be observed in ultracold atoms, thus offering an alternative way of probing the dynamics of many-body systems.",
"revisions": [
{
"version": "v1",
"updated": "2018-05-16T17:50:57.000Z"
}
],
"analyses": {
"keywords": [
"open cold-atom systems",
"particle-current variance",
"many-body multi-valuedness",
"open interacting fermionic systems",
"lissajous curve"
],
"note": {
"typesetting": "TeX",
"pages": 5,
"language": "en",
"license": "arXiv",
"status": "editable"
}
}
}