Even-odd entanglement in boson and spin systems

التفاصيل البيبلوغرافية
العنوان: Even-odd entanglement in boson and spin systems
المؤلفون: Rossignoli, Raul, Canosa, Norma, Matera, Juan Mauricio
المصدر: Phys. Rev. A 83, 042328 (2011)
سنة النشر: 2011
المجموعة: Condensed Matter
Quantum Physics
مصطلحات موضوعية: Quantum Physics, Condensed Matter - Statistical Mechanics
الوصف: We examine the entanglement entropy of the even half of a translationally invariant finite chain or lattice in its ground state. This entropy measures the entanglement between the even and odd halves (each forming a "comb" of $n/2$ sites) and can be expected to be extensive for short range couplings away from criticality. We first consider bosonic systems with quadratic couplings, where analytic expressions for arbitrary dimensions can be provided. The bosonic treatment is then applied to finite spin chains and arrays by means of the random phase approximation. Results for first neighbor anisotropic XY couplings indicate that while at strong magnetic fields this entropy is strictly extensive, at weak fields important deviations arise, stemming from parity-breaking effects and the presence of a factorizing field (in which vicinity it becomes size-independent and identical to the entropy of a contiguous half). Exact numerical results for small spin s chains are shown to be in agreement with the bosonic RPA prediction.
Comment: 10 pages, 4 figures
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevA.83.042328
URL الوصول: http://arxiv.org/abs/1104.4005
رقم الانضمام: edsarx.1104.4005
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevA.83.042328