Ferromanyetik Rezonans Tekniği Kullanılarak Cu/Ni/Cu İnce Filmlerde Ara Katman Kalınlığının Etkisinin İncelenmesi

Öz

Bu çalışma, Cu/Ni/Cu çok katmanlı ince filmlerde Ni katmanının kalınlığının manyetik davranış üzerindeki etkisini incelemektedir. Ferromanyetik rezonans kullanarak çeşitli Ni kalınlıklarında rezonans alanını ölçtük. Anizotropi, spin saçılması ve hem yüzey hem de arayüz etkileri de dahil olmak üzere önemli manyetik özelliklerin ara katmanın kalınlığı tarafından belirlendiği gözlemlendi. Daha ince Ni filmlerinde yüzey etkileri baskınken, daha büyük katmanlarda hacimsel manyetik davranış daha yaygındır. Manyetik özellik kontrolünün esas olduğu spintronik için çok katmanlı yapıların tasarımı bu bulgulara dayanmaktadır. Çalışmanın FMR sonuçları, Cu/Ni/Cu çok katmanlı ince filmlerdeki manyetik anizotropinin Ni katmanının kalınlığından önemli ve doğrusal olmayan bir şekilde etkilendiğini göstermektedir. İncelenen örneklerde, kolay manyetizasyon ekseninin Ni kalınlığı 2,4 ve 2,8 nm'de düzlem dışı olduğu, kalınlık 3,2 nm'ye çıktığında ise sistemin düzlem içi manyetik anizotropi sergilediği bulunmuştur. Bununla birlikte, Ni kalınlığı 4,0 nm'ye çıkarıldığında kolay eksen düzlem içi yönelimini korumuştur. Bu davranış, artan kalınlıkla tek yönlü olarak gerçekleşen ve literatürde yaygın olarak belgelenen klasik spin yeniden yönlendirme geçişleriyle aynı değildir. Bu, çok katmanlı sistemlerde manyetik performansın doğru bir şekilde ayarlanmasının mümkün olduğunu göstermektedir.

Anahtar Kelimeler

• Ferromanyetik Rezonans Tekniği
• CuNiCu
• Çok Katmanlı İnce Filmler
• Manyetik Özellikler
• Ara Katman

Investigation of the Effect of Spacer Layer Thickness on Cu/Ni/Cu Thin Films Using Ferromagnetic Resonance Technique

Öz

This work examines the effects of Ni layer thickness on magnetic behaviour in Cu/Ni/Cu multilayer thin films. We measured the resonance field across a variety of Ni thicknesses using ferromagnetic resonance. It was observed that important magnetic properties, including anisotropy, spin scattering, and both surface and interfacial effects, are determined by the thickness of the interlayer. Surface effects dominate with thinner Ni films, but volume magnetic behaviour is more prevalent with larger layers. The design of multilayer structures for spintronics, where magnetic property control is essential, is guided by these findings. The study's FMR results demonstrate that magnetic anisotropy in Cu/Ni/Cu multilayer thin films is significantly and nonlinearly influenced by the thickness of the Ni layer. In the investigated samples, the easy magnetization axis was found out of plane at a Ni thickness of 2.4 and 2.8 nm, and as the thickness increased to 3.2 nm, it was found that the system displayed in plane magnetic anisotropy. Nevertheless, the easy axis remained in the in-plane orientation when the Ni thickness was raised to 4.0 nm. This behaviour is not the same as the classical spin reorientation transitions, which happen unidirectionally with increasing thickness and are commonly documented in the literature. This suggests that it is possible to accurately tune the magnetic performance in multilayer systems.

Anahtar Kelimeler

• Ferromagnetic Resonance Technique
• CuNiCu
• Multilayered Thin films
• Magnetic Properties
• Spacer Layer

Kaynakça

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