Properties of Josephson junction fabricated on bicrystal substrate with different misorientation angles

In order to develop YBa2Cu3O7-delta bicrystal junctions suitable for high-performance superconducting quantum interference device (SQUID), the relationship between the junction properties and the misorientation angle of the bicrystal substrate is studied experimentally. Misorientation angles of 24 degrees, 27 degrees, 30 degrees, 33 degrees and 36.8 degrees are used, and the angular dependencies of junction resistance R-s and critical current I-o are investigated. It is shown that values of R-s and I-o approximately follow the relation IoRs1.5=const. in these junctions. The obtained results are analyzed in terms of the direct and resonant tunneling mechanisms. It is also shown that values of R(s)approximate to 10 Ohm and I(o)approximate to 20 mu A can be obtained rather reproducibly when we use the 30 degrees junctions. The properties of this junction are very promising for the development of high-performance SQUID.