Macroscopic ground-state degeneracy and magnetocaloric effect in the exactly solvable spin-1/2 Ising–Heisenberg double-tetrahedral chain

Publication date: Available online 14 June 2018Source: Physics Letters AAuthor(s): Lucia Gálisová, Dušan KnežoAbstractThe ground-state degeneracy and magnetocaloric effect in the spin-1/2 Ising–Heisenberg double-tetrahedral chain are exactly investigated. It is demonstrated that the zero-temperature phase diagram involves two classical and two quantum chiral phases with distinct degrees of the macroscopic degeneracy. Different macroscopic degeneracies observed in the latter phases and at individual ground-state phase transitions are confirmed by multiple-peak dependencies of the specific heat and entropy on the magnetic field. The cooling capability of the model is well illustrated by the magnetic-field variations of the isothermal entropy change, temperature isotherms and the magnetic Grüneisen parameter.

Source: Physics Letters A - July 10, 2018 Category: Physics Source Type: research