Magnon-impurity interaction effect on the magnonic heat capacity of the Lieb lattice

In this paper, we theoretically address the magnonic heat capacity of charged impurity-infected infinite 2D Lieb lattice with new interesting features to be seen. The dynamics of non-interacting and interacting magnons are described by the Heisenberg model, the Born approximation, and the Green’s function technique. The used model consists of three potentials, satisfying the experiment requirements: (i) the Dzyaloshinskii-Moriya interaction (DMI), (ii) the next-nearest-neighbors (NNN) coupling, and (iii) the Zeeman magnetic field. We show that the magnonic heat capacity increases with the charged impurity concentration and/or the scattering potential. We realized that the infecting the system with different impurity atoms yields the higher magnonic heat capacity than the same ones. Furthermore, we show that both normal and perturbed magnonic heat capacities do not alter for heavy atomic nuclei. The obtained numerical data state that the efficient magnonic heat capacity occurs at short-range potentials and do not change for longer-range ones. This manifest itself at long-ranges as a plateau for DMI potential and the oscillatory accompanied with decay trends for NNN coupling and the Zeeman magnetic field. Finally, we observe the non-monotonic and non-symmetric behaviors for heat capacity when Zeeman magnetic field is parallel and/or antiparallel to the host spins.