Coherence in magnetic quantum tunneling
| dc.creator | Fernandez, Julio F. | |
| dc.date | 2001-10-25 | |
| dc.date.accessioned | 2026-07-07T02:43:17Z | |
| dc.date.available | 2026-07-07T02:43:17Z | |
| dc.description | Currently, spin tunneling at very low temperatures is assumed to proceed as an incoherent sequence of events that take place whenever a bias field h(t) that varies randomly with time t becomes sufficiently small, as in Landau-Zener transitions. We study the behavior of a suitably defined coherence time t_p. Coherence effects become significant when t_p >= t_h$, where t_h is the correlation time for h(t). The theory of tunneling of Prokof'ev and Stamp (PS), which rests on the assumption that t_p <= t_h, is extended beyond this constraint. It is shown, both analytically and numerically, that t_p >= t_h when t_h*dh <= h, where dh is the rms deviation of h. Equations that give t_p and the tunneling rate as a function of t_h*dh both for t_h*dh>=h, where the theory of PS hold, and for t_h*dh <= h, where it does not, are derived. | |
| dc.description | 4 pages, 3 figures | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0110540 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0110540 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/18437 | |
| dc.subject | Mesoscale and Nanoscale Physics | |
| dc.subject | Statistical Mechanics | |
| dc.title | Coherence in magnetic quantum tunneling | |
| dc.type | text |