Characterizing localization properties of two spinless electrons in a one-dimensional Harper model with concurrence

• 来源期刊: 中国物理B（英文版）
• 关键词: entanglement two interacting particles localization Harper model
• 年，卷（期）: 2008,（2）
• 页码范围: 674-679
• 页数: 6页
• 语种: 英文

摘要

By mapping the Fock space of many local fermionic modes isomorphically onto a many-qubit space and using the measure of concurrence,this paper studies numerically the mode entanglement of two spinless electrons with on-site interaction U moving in the one-dimensional Harper model.Generally speaking,for electrons in extended regimes (potential parameter λ＜ 2),the spectrum-averaged concurrence N<C> first decreases slowly as λ increases until its local minimum,then increases with λ until its peak at λ = 2,while for electrons in localized regimes (λ＞ 2),N<C>decreases drastically as λ increases.The functions of N<C> versus λ are different for electrons in extended and localized regimes.The maximum of N<C>occurs at the point λ = 2,which is the critical value in the one-dimensional singleparticle Harper model.From these studies it can distinguish extended,localized and critical regimes for the two-particle system.It is also found for the same λ that the interaction U always induce the decreases of concurrence,i.e.,the concurrence can reflect the localization effect due to the interaction.All these provide us a new quantity to understand the localization properties of eigeustates of two interacting particles.