Research Article

The Stratified Superconductivity in Ba0.6K0.4BiO3 Single Crystal: Direct Measurement of Energy Gap between Homo-, and Inhomogeneous States

Figure 3

Current-voltage characteristics of ceramic sample at different temperatures and magnetic fields: (a) = 4.8 K: 1; = 0 T, 2; 0.64 T, 3; 1.6 T, 4; 3.2 T, 5; 4.8 T, and 6; 6.4 T; (b) = 0 T: 1; T = 4,8 K, 2; 10 K, 3; 15 K, 4; 18 K, and 5; 22 K. On inset to (a) the dependence of the critical current versus magnetic field, built from hysteretic curves on (a), is given. Top inset to (b): the nonmonotone dependence of the critical current versus temperature, with maximum at  K. Bottom inset to (b): the effect of suppression of critical current under the action of microwave radiation, which demonstrates possible presence of Josephson properties of system below .
317974.fig.003a
(a)
317974.fig.003b
(b)