Materials, Methods & Technologies, Volume 4, 2010

Rezumat: In this work, the influence of the anharmonic current phase dependence on the properties of weak links of the Josephson type (WLJT) is considered. The introduction of the anharmonicity coefficient k develops the model of the anharmonic current phase dependence of weak links, j(φ) = jc [sin φ - sin(kφ)/k]. It is established that, in WLJT, the anharmonic current phase dependence increases the plasma frequency. A specific feature of the dependence of the supercurrent on the normalized magnetic flux is shown for weak links with anharmonic current phase dependence, namely, a peak at the normalized flux φ/φ0 = 0, as well as the appearance of minima at fractional values of the normalized flux φ/φ0. On the basis of modeling studies of plasma frequency dynamics, the occurrence of fractional Shapiro steps on the current voltage characteristic of Josephson structures with anharmonic current phase dependence under microwave irradiation is interpreted.