Quantum dynamics of double-qubits in a spin star lattice with an XY interaction
| dc.creator | Jing, Jun | |
| dc.creator | Lü, Zhi-Guo | |
| dc.date | 2006-12-14 | |
| dc.date | 2007-10-09 | |
| dc.date.accessioned | 2026-07-07T08:34:51Z | |
| dc.date.available | 2026-07-07T08:34:51Z | |
| dc.description | The dynamics of two coupled spins-1/2 interacting with a spin-bath via the quantum Heisenberg XY coupling is studied. The pair of central spins served as a quantum open subsystem are initially prepared in two types of states: the product states and the Bell states. The bath, which consists of $N$ (in the thermodynamic limit $N\to\infty$) mutually coupled spins-1/2, is in a thermal state at the beginning. By the Holstein-Primakoff transformation, the model can be treated effectively as two spin qubits embedded in a single mode cavity. The time-evolution of the purity, z-component summation and the concurrence of the central spins can be determined by a Laguerre polynomial scheme. It is found that (i) at a low temperature, the uncoupled subsystem in a product state can be entangled due to the interaction with bath, which is tested by the Peres-Horodecki separability; however, at a high temperature, the bath produces a stronger destroy effect on the purity and entanglement of the subsystem; (ii) when the coupling strength between the two central spins is large, they are protected strongly against the bath; (iii) when the interaction between the subsystem and the bath is strong, the collapse of the two spin qubits from their initial entangled state is fast. | |
| dc.description | 16 pages, 8 figures, submitted to JPA | |
| dc.identifier | https://arxiv.org/abs/quant-ph/0612115 | |
| dc.identifier | http://arxiv.org/abs/quant-ph/0612115 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/139578 | |
| dc.subject | Quantum Physics | |
| dc.title | Quantum dynamics of double-qubits in a spin star lattice with an XY interaction | |
| dc.type | text |