II. TİP ÜSTÜNİLETKENLERİN MİKRODALGA YÜZEY DİRENCİ ÜZERİNE AKI SÜRÜKLENMESİNİN ETKİSİ

Abstract

II. tip üstüniletkenlerde girdap hareketleri ile alakalı hala açık bazı sorunların çözümüne bir katkı olarak,

mikrodalga yüzey direncinde akı sürüklenmesinin alan bağlılığı üzerine teorik bir çalışma

gerçekleştirilmiştir. Akım yoğunluğunun alan bağlılığı için Anderson ve Kim tarafından önerilen ve akı

sürüklenmesini içeren bir teori ile mikrodalga yüzey direncinin hesaplanması için Bonura ve ark.

tarafından önerilen bir model kullanılmıştır. Sonuçlar, sürüklenme etkisi düşünülerek mikrodalga yüzey

direncinin kritik hal modeli ile hesaplanabileceğini ve histerezis çevrimlerinin çivilenme parametresine

güçlü bir şekilde bağlı olduğunu göstermiştir.

Keywords

• Mikrodalga (md) yüzey direnci,akı sürüklenmesi,Kritik hal modeli,II. Tip üstüniletkenler

EFFECT OF FLUX CREEP ON MICROWAVE SURFACE RESISTANCE OF TYPE-II SUPERCONDUCTORS

Abstract

In an attempt to contribute to solving some still open problems concerning the vortex motion in type- II

superconductors, a theoretical study has been carried out for field dependence of the flux creep in

microwave surface resistance. It uses a theory proposed by Anderson and Kim for the field dependence of

current density with creep effect and a model suggested by Bonura et al. for the microwave surface

resistance. Results shows that, by considering creep effect, the microwave surface resistance can be

calculated with the critical state model and the hysteresis strongly depends on the pinning parameter.

Keywords

• Microwave (mw) surface resistance,flux creep,critical state models,type II superconductors

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