Observation of an extended magnetic field penetration in amorphous superconducting MoGe films

アモルファスMoGe超伝導フィルム内の磁場侵入観察

西尾 太一郎*; 岡安 悟  ; 鈴木 淳市; 小久保 伸人*; 門脇 和男*

Nishio, Taichiro*; Okayasu, Satoru; Suzuki, Junichi; Kokubo, Nobuhito*; Kadowaki, Kazuo*

アモルファスMoGe薄膜でさまざまな膜厚の試料で単一磁束量子による磁場分布を走査型SQUID顕微鏡で観察した。膜厚が磁場侵入長より薄い薄膜では、磁場分布は実効的な磁場侵入長=2/によって記述され、Pearlの予言に従うことが明らかになった。またの温度依存性は2流体モデルで説明できる。

We have observed the magnetic field distribution of a vortex generated in amorphous ()-MoGe thin films with various thicknesses () (, where is the penetration depth) with a scanning SQUID microscope. From analyses of the field distribution as functions of the film thickness and temperature, it is found that an effective in-plane penetration depth () extends with descreasing d, in accordance with the Pearl's prediction =2/. Temperature dependence of is also consistent with the two-fluid model involving the Pearl's prediction.