Narrow long Josephson junctions

Long Josephson junctions of width down to less than 0.3 mu m are fabricated using electron beam lithography. The junctions are made in niobium-aluminu m-oxide trilayer technology using cross-linked PMMA for insulation. We meas ured the fluxon penetration field, the magnetic field period of the critica l current modulation, and the Fiske step voltages of the junctions. A stron g dependence of these quantities on the junction width is observed. Assumin g a general-type relation between the spatial derivative of the phase and t he spatial variation of the magnetic field along the plane of the junction, we derive a scaling relation between the measured quantities depending on the junction width. The derived relation is consistent with the experimenta l data.