Landau-Zener transition of a two-level system driven by spin chains near their critical points
School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian, 116024, P.R. China
Published online: 12 October 2007
The Landau-Zener (LZ) transition of a two-level system coupling to spin chains near their critical points is studied in this paper. Two kinds of spin chains, the Ising spin chain and XY spin chain, are considered. We calculate and analyze the effects of system-chain coupling on the LZ transition. A relation between the LZ transition and the critical points of the spin chain is established. These results suggest that LZ transitions may serve as the witnesses of criticality of the spin chain. This may provide a new way to study quantum phase transitions as well as LZ transitions.
PACS: 32.80.Bx – Level crossing and optical pumping / 03.65.Yz – Decoherence; open systems; quantum statistical methods / 05.70.Jk – Critical point phenomena / 05.50.+q – Lattice theory and statistics
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2007