Malzeme Biliminde Gelişmeler Yarı Metalik Heusler Alaşımlarının Yapısal Manyetik ve Enerji Spintronik Teknolojilerindeki Yenilikler

Year 2025, Volume: 20 Issue: 2, 541 - 550, 30.09.2025

Ece Kalay , İskender Özkul , Ömer Güler , Canan Aksu Canbay

https://doi.org/10.55525/tjst.1654241

Abstract

Yarı metalik Heusler alaşımları, spintronik ve termoelektrik uygulamalar için büyük potansiyele sahip malzemelerdir. Bu alaşımlar, bir spin yönünde metalik iletkenlik gösterirken diğer spin yönünde yalıtkan gibi davranarak %100’e yakın spin kutuplaşması sağlar. Bu özellik, manyetik tünel eklemleri (MTJ’ler), manyetik rastgele erişimli bellekler ve spin bazlı transistörler gibi spintronik cihazlar için kritik öneme sahiptir. Bu çalışma, Heusler alaşımlarının elektronik, manyetik ve yapısal özelliklerini inceleyerek üretim yöntemleri, atomik düzenlenme ve yoğunluk fonksiyonel teorisi (DFT) ile modellenmesine odaklanmaktadır. DFT tabanlı hesaplamalar, bant yapıları, spin kutuplaşması ve manyetik özelliklerin tahmin edilmesinde önemli bir araçtır. Ayrıca, düzensizlik, gerilim ve bileşim değişimlerinin malzeme özellikleri üzerindeki etkisi analiz edilerek performans optimizasyonu stratejileri ele alınmaktadır. Heusler alaşımlarının spintronik bellek cihazları, termoelektrik enerji dönüşümü ve kuantum teknolojilerinde kullanım potansiyeli değerlendirilmektedir. Teorik ve deneysel yaklaşımların birleştirilmesiyle, bu malzemelerin ileri teknoloji uygulamalarındaki rolüne dair kapsamlı bir bakış sunulmaktadır.

Keywords

Yarı metaller , Heusler alaşımları , spintronik , manyetik özellikler , yoğunluk fonksiyonel teorisi

Advances in Materials Innovations in Half Metallic Heusler Alloys for Structural Magnetic and Energy Spintronic Technologies

Abstract

Half-metallic Heusler alloys are promising materials for spintronic and thermoelectric applications. These alloys exhibit metallic conductivity in one spin direction while acting as insulators in the opposite spin direction, enabling nearly 100% spin polarization. This property is crucial for spintronic devices such as magnetic tunnel junctions (MTJs), magnetic random-access memories, and spin-based transistors. This study investigates the electronic, magnetic, and structural properties of Heusler alloys, focusing on their synthesis methods, atomic ordering, and modelling via density functional theory (DFT). DFT-based calculations serve as a key tool for predicting band structures, spin polarization, and magnetic properties. Additionally, the effects of disorder, strain, and compositional changes on material properties are analysed to explore performance optimization strategies. The potential applications of Heusler alloys in spintronic memory devices, thermoelectric energy conversion, and quantum technologies are also discussed. This work is presented as a review article and systematically compiles and interprets findings from the existing literature to provide a broad understanding of the topic. By integrating theoretical and experimental approaches, this study provides a comprehensive overview of the role of these materials in advanced technological applications.

Keywords

Half-metals , Heusler alloys , spintronics , magnetic properties , density functional theory

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