Vortex states in superconducting rings

The superconducting state of a thin superconducting disk with a hole is studied within the non-linear Ginzburg-Landau theory in which the demagnetization effect is accurately taken into account. We find that the flux through the hole is not quantized, the superconducting state is stabilized with increasing size of the hole for fixed radius of the disk, and a transition to a multi-vortex state is found if the disk is sufficiently large. Breaking the circular summetry through a non central location of the hole in the disk enhances the multi-vortex state.Comment: 11 pages, 23 figures (postscript). To appear in Physical Review B, Vol. 61 (2000

Investigation of the barium strontium titanate films on the silicon substrate

A study of the electrical and photoelectric properties of the heterostructure of barium strontium titanate film on a silicon substrate was performed. The conductivity of the heterostructure significantly increased and the capacitance decreased with frequency. The photoconductivity significantly increased for the sample modified by Cr+ ion implantation. The temperature dependence of the resistance under green laser irradiation demonstrated maxima at 150 K

Properties of the barium strontium titanate film on the silicon substrate

© 2020, © 2020 Taylor & Francis Group, LLC. A study of the optical, electrical, and photoelectric properties of the heterostructure of barium strontium titanate film on a silicon substrate was performed. An intense maximum is observed in the absorption spectrum of the heterostructure at 410 nm. The conductivity of the heterostructure significantly increases and the capacitance drops with increasing frequency. Photostimulated conductivity measurement showed that the intensity of photoconductivity significantly increased for the sample modified by Cr+ ion implantation. The temperature dependence of the resistance under UV and green laser irradiation showed maxima at 100 and 150 K, and then the resistance decreased with increasing temperature