Reentrant behaviors in the phase diagram of spin-1 planar ferromagnet with single-ion anisotropy
Autor: | L. De Cesare, Maria Teresa Mercaldo, A. Caramico D'Auria, I. Rabuffo |
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Rok vydání: | 2018 |
Předmět: |
Quantum phase transition
02 engineering and technology 01 natural sciences Planar ferromagnet Quantum criticality Quantum critical point 0103 physical sciences Electronic Optical and Magnetic Materials Electrical and Electronic Engineering 010306 general physics Anisotropy Phase diagram Physics Condensed matter physics Two-time Green's functions Decoupling (cosmology) Reentrant phenomena 021001 nanoscience & nanotechnology Condensed Matter Physics Electronic Optical and Magnetic Materials Magnetic field Single-ion anisotropy Exchange bias Ferromagnetism 0210 nano-technology |
Zdroj: | Physica B: Condensed Matter. 536:422-426 |
ISSN: | 0921-4526 |
Popis: | We used the two-time Green function framework to investigate the role played by the easy-axis single-ion anisotropy on the phase diagram of ( d > 2 )-dimensional spin-1planar ferromagnets, which exhibit a magnetic field induced quantum phase transition. We tackled the problem using two different kind of approximations: the Anderson-Callen decoupling scheme and the Devlin approach. In the latter scheme, the exchange anisotropy terms in the equations of motion are treated at the Tyablikov decoupling level while the crystal field anisotropy contribution is handled exactly. The emerging key result is a reentrant structure of the phase diagram close to the quantum critical point, for certain values of the single-ion anisotropy parameter. We compare the results obtained within the two approximation schemes. In particular, we recover the same qualitative behavior. We show the phase diagram, close to the field-induced quantum critical point and the behavior of the susceptibility for different values of the single-ion anisotropy parameter, enhancing the differences between the two different scenarios (i.e. with and without reentrant behavior). |
Databáze: | OpenAIRE |
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