11188

10294

كارشناسي ارشد

ماده چگال

اصفهان:دانشگاه صنعتي اصفهان، دانشكده فيزيك

1394

هشت، 142ص.: مصور

علي اكبر بابايي بروجني

پيمان صاحب سرا

فرهاد فضيله، حميده شاكري پور

1395/01/30

فيزيك

ID10294

AbstractIn this study based on the validity of superconducting critical state model two systems one a superconducting system of multiple thin strips and the other SQUID practicallythe system that includes vertical and horizontal superconductivity strips are studied e systems have been studied under free bulk pinning assumption e systems haveplaced in a perpendicular magnetic eld whi is increased gradually We obtain themagnetic eld and current density distributions by increasing the eld in ea step andwe draw the magnetization curve of related systems e comparison of magnetizationcurve shows that by raising the number of strips and displacing the strips the geo metrical barrier of systems increases and this barrier prevents the complete repulsionof magnetic ux of system erefore the magnetization become larger the magnetichysteresis increases and the additional kinks appear in the magnetization curve e magnetic ux focusing and the role of gaps in exclusion of ux is obtained bycalculating the so called e ective area e e ective area curves of the systems showthat by raising the number of strips the total ux passing through the slots increases For low external magnetic eld the slope of e ective area is ascending and then isdescending for the higher applied magnetic eld In conclusion the decrease of focusinge ects is unfavorable for the SQUID But we are interested in investigating the e ectivearea with ascendant slope We saw this feature just in centeral slit of systems with evenstrips e comparison of systems show that by raising the number of strips the passing ux from centeral gap increases Keywords Type II superconductivity multiple strips system e ective area magneti zation kink points

علي اكبر بابايي بروجني

پيمان صاحب سرا

فرهاد فضيله، حميده شاكري پور