arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1911.04595cond-mat.stat-mechcond-mat.str-elquant-ph
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自由费米子和量子自旋链中作为缺陷问题的观测量的形成概率和统计

Formation probabilities and statistics of observables as defect problems in the free fermions and the quantum spin chains

M. N. Najafi, M. A. Rajabpour

摘要:

我们证明了二次费米子哈密顿量中组态基的形成几率(FP)和观测量的全计数统计量(FCS)的计算等价于含亏损哈密顿量中空性形成几率(EFP)的计算.特别地,我们首先证明了在基态中寻找特定构型的FP等价于具有亏损的二次哈密顿量的基态的EFP。然后,我们发现,找到一个特定的值的任何二次观测的概率是等价的FP问题,并最终导致计算EFP的基态的哈密顿量的缺陷。我们提供了新的确切行列式公式的FP在一般的二次费米子哈密顿量。作为我们的形式主义的应用程序,我们研究的粒子和扭结的数量的统计。我们的结论也可以推广到量子自旋链,它可以通过Jordan-Wigner(J-W)变换映射到自由费米子。特别是,我们提供了一个精确的解决方案的横向场XY链与交错线缺陷的问题。我们还研究了横向场XY链中的磁化强度和扭结的分布,并展示了这些量的对偶性质如何在分布中表现出来。

英文摘要:

We show that the computation of formation probabilities (FP) in the configuration basis and the full counting statistics (FCS) of observables in the quadratic fermionic Hamiltonians are equivalent to the calculation of emptiness formation probability (EFP) in the Hamiltonian with a defect. In particular, we first show that the FP of finding a particular configuration in the ground state is equivalent to the EFP of the ground state of the quadratic Hamiltonian with a defect. Then, we show that the probability of finding a particular value for any quadratic observable is equivalent to a FP problem and ultimately leads to the calculation of EFP in the ground state of a Hamiltonian with a defect. We provide new exact determinant formulas for the FP in the generic quadratic fermionic Hamiltonians. As applications of our formalism we study the statistics of the number of particles and kinks. Our conclusions can be extended also to the quantum spin chains that can be mapped to the free fermions via Jordan-Wigner (J-W) transformation. In particular, we provide an exact solution to the problem of the transverse field XY chain with a staggered line defect. We also study the distribution of magnetization and kinks in the transverse field XY chain and show how the dual nature of these quantities manifest itself in the distributions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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