Defect generation in a spin-1/2 transverse XY chain under repeated quenching of the transverse field
| dc.creator | Mukherjee, Victor | |
| dc.creator | Dutta, Amit | |
| dc.creator | Sen, Diptiman | |
| dc.date | 2008-03-10 | |
| dc.date | 2008-07-22 | |
| dc.date.accessioned | 2026-07-07T09:51:38Z | |
| dc.date.available | 2026-07-07T09:51:38Z | |
| dc.description | We study the quenching dynamics of a one-dimensional spin-1/2 $XY$ model in a transverse field when the transverse field $h(=t/τ)$ is quenched repeatedly between $-\infty$ and $+\infty$. A single passage from $h \to - \infty$ to $h \to +\infty$ or the other way around is referred to as a half-period of quenching. For an even number of half-periods, the transverse field is brought back to the initial value of $-\infty$; in the case of an odd number of half-periods, the dynamics is stopped at $h \to +\infty$. The density of defects produced due to the non-adiabatic transitions is calculated by mapping the many-particle system to an equivalent Landau-Zener problem and is generally found to vary as $1/\sqrtτ$ for large $τ$; however, the magnitude is found to depend on the number of half-periods of quenching. For two successive half-periods, the defect density is found to decrease in comparison to a single half-period, suggesting the existence of a corrective mechanism in the reverse path. A similar behavior of the density of defects and the local entropy is observed for repeated quenching. The defect density decays as $1/{\sqrtτ}$ for large $τ$ for any number of half-periods, and shows a increase in kink density for small $τ$ for an even number; the entropy shows qualitatively the same behavior for any number of half-periods. The probability of non-adiabatic transitions and the local entropy saturate to 1/2 and $\ln 2$, respectively, for a large number of repeated quenching. | |
| dc.description | 5 pages, 3 figures | |
| dc.identifier | https://arxiv.org/abs/0803.1351 | |
| dc.identifier | http://arxiv.org/abs/0803.1351 | |
| dc.identifier | Phys. Rev. B 77, 214427 (2008) | |
| dc.identifier | doi:10.1103/PhysRevB.77.214427 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/165317 | |
| dc.subject | Statistical Mechanics | |
| dc.subject | Quantum Physics | |
| dc.title | Defect generation in a spin-1/2 transverse XY chain under repeated quenching of the transverse field | |
| dc.type | text |