Portal de Periódicos da CAPES

Frequency Dependence of AC Josephson Effect in Point-Contact (Y, Er) BaCuO/Nb

1987; Institute of Physics; Volume: 26; Issue: 8A Linguagem: Inglês

10.1143/jjap.26.l1353

1347-4065

Sadamu Kita, Hisao Tanabe, Tetsuro Takahashi, Masayoshi Tonouchi, Yasufumi Fujiwara, Takeshi Kobayashi,

Advanced Condensed Matter Physics

Microwave and millimeterwave dependences of ac Josephson effect were investigated in YBaCuO ceramic superconductors. We observed very clear constant-voltage steps (Shapiro steps) on the current-voltage curve of YBaCuO/Nb junctions at signals of 14.1,25.5 and 35.0 GHz. The observed step voltages were frequency dependent in accordance with the ( h /2 e ) f rule. This strongly suggests that pair-electrons serve as the superconducting particle even in ceramic materials. In addition, the ac Josephson effect was also observed in point-contact ErBaCuO ceramics containing a magnetic element Er.