2015/12/10 by Jozef Strecka, Jozef Strečka, Raphael Cavalcante Alecio +4 · 1 citation
Computer Science · Physics and Astronomy · #Antiferromagnetism #Concurrence #Condensed matter physics #Degenerate energy levels #Frustration #Ground state #Heisenberg model #Ising model #Physics #Quantum #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum entanglement #Quantum many-body systems #Quantum mechanics #Spin (aerodynamics) #Thermodynamics #cond-mat.stat-mech #cond-mat.str-el
paper · pdf · doi:10.1016/j.jmmm.2016.02.095
published as J. Magn. Magn. Mater. 409 (2016) 124-133 · 14 pages, 11 figures
arxiv created 2015/12/10 · openalex publication_date 2016/03/02 · arxiv updated 2016/12/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The spin-1/2 Ising-Heisenberg three-leg tube composed of the Heisenberg spin triangles mutually coupled through the Ising inter-triangle interaction is exactly solved in a zero magnetic field. By making use of the local conservation for the total spin on each Heisenberg spin triangle the model can be rigorously mapped onto a classical composite spin-chain model, which is subsequently exactly treated through the transfer-matrix method. The ground-state phase diagram, correlation functions, concurrence, Bell function, entropy and specific heat are examined in detail. It is shown that the spin frustration represents an indispensable ground for a thermal entanglement, which is quantified with the help of concurrence. The specific heat displays diverse temperature dependences, which may include a sharp low-temperature peak mimicking a temperature-driven first-order phase transition. It is convincingly evidenced that this anomalous peak originates from massive thermal excitations from the doubly degenerate ground state towards an excited state with a high macroscopic degeneracy due to chiral degrees of freedom of the Heisenberg spin triangles.