Distribution of a bipartite entanglement in a mixed spin-(1/2,1) Heisenberg tetramer

Abstract: The distribution of bipartite entanglement in a mixed spin-(1/2,1) Heisenberg tetramer composed from two spin-1/2 and two spin-1 entities is investigated in detail in presence of an external magnetic field. Four different negativities measuring a strength of bipartite entanglement are analyzed at zero and non-zero temperatures. Derived rigorous analytic results and respective numerical results are discussed with the particular emphasis laid on the significance of a strength of the pair spin-spin interactions and spin diversity in the entanglement description. Based on both aforementioned driving forces the regions of parametric space, where the bipartite entanglement can exist solely for one type of spin pair or all four spin pairs, were identified.