Magnetic-field-induced quantum criticality in a planar ferromagnet with single-ion anisotropy

17th International Conference on Recent Progress in Many-Body Theories

Mercaldo, M.T.^1 ; Rabuffo, I.^1 ; De Cesare, L.^2 ; D'Auria, A. Caramico^2

Dipartimento di Fisica E. R. Caianiello, Università di Salerno, I-84084 Fisciano (Salerno), Italy^1

Dipartimento di Fisica, Università di Napoli Federico II, I-80125 Napoli, Italy^2

关键词: Andersons;    External magnetic field;    Ferromagnets;    Nonthermal;    Quantum critical points;    Quantum criticality;    Quantum phase transitions;    Single ion anisotropy;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/529/1/012019/pdf
DOI  :  10.1088/1742-6596/529/1/012019

来源: IOP

【 摘 要 】

We analyze the effects induced by single-ion anisotropy on quantum criticality in a d-dimensional spin-3/2 planar ferromagnet. To tackle this problem we employ the two-time Green's function method, using the Tyablikov decoupling for exchange interactions and the Anderson-Callen decoupling for single-ion anisotropy. In our analysis the role of non-thermal control parameter which drives the quantum phase transition is played by a longitudinal external magnetic field. We find that the single-ion anisotropy has substantial effects on the structure of the phase diagram close to the quantum critical point.