Spin Precession and Real Time Dynamics in the Kondo Model: A Time-Dependent Numerical Renormalization-Group Study
| dc.creator | Anders, Frithjof B. | |
| dc.creator | Schiller, Avraham | |
| dc.date | 2006-04-21 | |
| dc.date.accessioned | 2026-07-07T07:36:13Z | |
| dc.date.available | 2026-07-07T07:36:13Z | |
| dc.description | A detailed derivation of the recently proposed time-dependent numerical renormalization-group (TD-NRG) approach to nonequilibrium dynamics in quantum impurity systems is presented. We demonstrate that the method is suitable for fermionic as well as bosonic baths. A comparison with exact analytical results for the charge relaxation in the resonant-level model and for dephasing in the spin-boson model establishes the accuracy of the method. The real-time dynamics of a single spin coupled to both types of baths is investigated. We use the TD-NRG to calculate the spin relaxation and spin precession of a single Kondo impurity. The short- and long-time dynamics is studied as a function of temperature in the ferromagnetic and antiferromagnetic regimes. The short-time dynamics agrees very well with analytical results obtained at second order in the exchange coupling $J$. In the ferromagnetic regime, the long-time spin decay is described by the scaling variable $x = 2ρ_F J(T) T t$. In the antiferromagnetic regime it is governed for $T < T_K$ by the Kondo time scale $1/T_K$. Here $ρ_F$ is the conduction-electron density of states and $T_K$ is the Kondo temperature. Results for spin precession are obtained by rotating the external magnetic field from the x axis to the z axis. | |
| dc.description | Revtex, 21 pages, 11 figures, 1 table | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0604517 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0604517 | |
| dc.identifier | Phys. Rev. B 74, 245113 (2006) | |
| dc.identifier | doi:10.1103/PhysRevB.74.245113 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/120349 | |
| dc.subject | Strongly Correlated Electrons | |
| dc.subject | Mesoscale and Nanoscale Physics | |
| dc.title | Spin Precession and Real Time Dynamics in the Kondo Model: A Time-Dependent Numerical Renormalization-Group Study | |
| dc.type | text |