Bizmut adsorbe eden çinko oksit nanotellerin manyetik işlevselleşmesi

Yıl 2017, , 1448 - 1453, 01.12.2017

Sümeyra Güler Kılıç , Mehmet Aras

https://doi.org/10.16984/saufenbilder.304190

Öz

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

Öz

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.

Anahtar Kelimeler

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

Kaynakça

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