Ru2FeGa Heusler alaşımının yapısal, elektronik, elastik ve fonon özelliklerinin ilk prensip çalışması

Öz

Heusler tipi alaşımlar ferromanyetiktir ve ilginç manyetik özellikler göstermelerinden dolayı spin-elektronik ve magneto-elektronik uygulamalar için ideal malzeme grubudur. L2₁ kristal yapısındaki Ru₂FeGa Heusler alaşımının yapısal, elektronik, elastik ve fonon özellikleri, yoğunluk fonksiyonel teorisi (DFT) içerisinde genelleştirilmiş eğim yaklaşımı (GGA) metodu kullanılarak analiz edildi. Ru₂FeGa alaşımının hesaplanan örgü sabiti ve manyetik momenti, teorik sonuç ile iyi bir şekilde uyumludur. Bant yapısının analizi, Ru₂FeGa’nın metalik olduğunu ortaya koymaktadır. Ayrıca, bu alaşım için Bulk modülü (B), Shear modülü (G), B/G oranı, Young modülü (E) ve tek kristal elastik sabitler (C_ij) hesaplandı. Fonon dağılım eğrileri, yoğunluk fonksiyonel pertürbasyon teorisinin ilk prensip doğrusal tepki yaklaşımı kullanılarak elde edildi.

Anahtar Kelimeler

• Tam Heusler alaşımlar
• DFT
• elastik sabitler
• fonon eğrileri

First-Principle study of structural, electronic, elastic and phonon properties of Ru2FeGa Heusler alloy

Abstract

Heusler type alloys are ferromagnetic and are the ideal material for spin-electronic and magneto-electronic applications due to their interesting magnetic properties. The structural, electronic, elastic and phonon properties of the Ru₂FeGa Heusler alloy in L21 crystal structure have been analyzed handling density functional theory (DFT) in the Generalized Gradient Approximation (GGA) method. The calculated lattice constant and magnetic moment of Ru₂FeGa alloy is in good agreement with theoretical result. The analysis of the band structure reveal that Ru₂FeGa is metallic. Furthermore we also calculated the Bulk modulu (B), Shear modulu (G), B/G ratio, Young modulu (E) and unique-crystal elastic constants (C_ij) for this alloy. Phonon-dispersion curve has been obtained using the first principle linear-response touch of the density-functional perturbation theory.

Keywords

• Full Heusler alloys
• Density functional theory
• elastic constants
• phonon curves

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