Bizmut adsorbe eden çinko oksit nanotellerin manyetik işlevselleşmesi

Bizmut atomunun çinko oksit nanotelinin yüzeyine adsorpsiyonu Hubbard U düzeltmesi içeren yoğunluk-fonksiyonel hesaplamaları ile incelenmiştir. Birçok ekatom konfigürasyonları için geometri optimizasyonları gerçekleştirilerek, adsorpsiyon enerjileri ve manyetik momentler hesap edilmiştir. En düşük enerjili ekatom konfigürasyonu böylece belirlenmiştir. Bu konfigürasyonun bir eğik manyetik momente sahip olduğu bulunmuştur. Bu, manyetik moment vektörünün yönünün harici bir manyetik alan uygulanarak kontrol edilebileceği anlamına gelmektedir. Bant yapısı hesaplamaları bu öz manyetik momentin varlığının alt iletim bandı durumlarında değiş-tokuş yarılmasına neden olduğunu ortaya koymaktadır. Bu bulgular bizmut adsorpsiyonunun çinko oksit nanotellerinin manyetik işlevselleşmesine neden olduğunu göstermektedir.

Anahtar Kelimeler:

Eğik manyetik moment, Yoğunluk fonksiyonel teorisi, Çinko oksit, Nanotel, Adsorpsiyon, Bizmut

Magnetic functionalization of bismuth-adsorbing zinc oxide nanowires

The adsorption of bismuth atom on the surface of zinc oxide nanowires is investigated by carrying out density-functional calculations with Hubbard U correction. Geometry optimizations are performed for a number of adatom configurations, and the adsorption energies and magnetic moments are calculated. The lowest-energy adatom configuration is thus determined. It is found that this configuration possess a canted magnetic moment. This means that the orientation of the magnetic moment vector can be controlled by applying an external magnetic field. Band structure calculations reveal that the existence of this intrinsic magnetic moment causes a exchange splitting of the lower conduction band states. These findings show that the adsorption of bismuth leads to magnetic functionalization of zinc oxide nanowires.

Keywords:

Canted magnetic moment, Density functional theory, Zinc oxide, Nanowire, Adsorption, Bismuth,

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