2018/05/30 by Vimalesh Kumar Vimal, V. Subrahmanyam · 21 citations
Computer Science · Mathematics · Physics and Astronomy · #Advanced Condensed Matter Physics #Concurrence #Ground state #Ising model #Measure (data warehouse) #Physics #Quantum #Quantum and electron transport phenomena #Quantum discord #Quantum entanglement #Quantum many-body systems #Quantum mechanics #Squashed entanglement #cond-mat.str-el #cs.IT #math.IT #quant-ph
paper · pdf · doi:10.1103/physreva.98.052303
published in Physical Review A 98(5) (American Physical Society) · 14 pagers, 7 figures
arxiv created 2018/05/30 · openalex publication_date 2018/11/05 · arxiv updated 2018/11/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The entanglement and quantum correlation measures have been investigated for the ground state of a spin chain with a Kitaev-type exchange interactions on alternating bonds, along with a transverse magnetic field. There is a macroscopic degeneracy in the ground state for zero magnetic field, implying a quantum critical point. In this model, many entanglement and correlation measures, except the macroscopic multispecies entanglement measure, do not show true singular behavior in the vicinity of the critical point, as seen in the transverse-Ising model ground state and related models. We compute the pair concurrence measure of entanglement, the pair quantum discord to track the quantum correlations, and a global entanglement measure and a multispecies entanglement measure to investigate multiparty entanglement, both analytically and numerically. The nearest-neighbor concurrence shows a peak structure as a function of magnetic field, near the critical point, for various values of the ratio of interaction strengths, but its derivative does not show a singular behavior close to the critical point. A similar behavior is shown by the quantum discord and the global entanglement. The multispecies entanglement shows a clear signature of the critical point behavior, and the first-order derivative shows a divergence near zero magnetic field, for equal interaction strengths.