Karma Spin-1/2 ve Spin- 5/2 Heisenberg Ferrimanyetik Sistemin Manyetik Özellikleri

Yıl 2011, Cilt: 2 Sayı: 37, 25 - 32, 01.12.2011

Gülistan Mert

Öz

Kare örgüde karma spin- 2 1 ve spin- 2 5 Heisenberg ferrimanyetik sistemin manyetik davranışları, çift-zaman sıcaklık-bağımlı Green fonksiyon teorisi kullanılarak incelendi. En yakın ve ikinci en yakın komşu etkileşimlerinin ve tek-iyon anizotropisinin kompensasyon ve kritik sıcaklık üzerine etkisi incelendi. Sistem sadece en yakın komşu etkileşimi ve kristal alan içerdiğinde kompensasyon noktası gözlenmez. İkinci en yakın komşu etkileşimler dâhil edildiğinde ve belirli minimum bir değeri aştığı zaman kompensasyon noktası gözlenmektedir.

Anahtar Kelimeler

Karma spin Heisenberg model, ferrimanyetik sistem, Green fonksiyonu, kritik sıcaklık, kompensasyon sıcaklık

Magnetic Properties of a Mixed Spin-1/2 and Spin-5/2 Heisenberg Ferrimagnetic System

Öz

The magnetic behaviors of a mixed spin- 2 1 and spin- 2 5 Heisenberg ferrimagnetic system on a square lattice are studied by using the double-time temperature-dependent Green`s function technique. The influences of the nearest- and next-nearst-neighbor interaction and the single-ion anisotropy on compensation and critical temperature are studied. When the system includes only a nearest-neighbor interaction and the single-ion anisotropies, one does not observe a compensation point. When the next nearest-neighbor interactions are included and exceed a certain minimum value, a compensation point appears.

Anahtar Kelimeler

Mixed-spin Heisenberg model, ferrimagnetic system, Green`s function, Critical temperature, Compensation temperature

Kaynakça

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