Year: 2026
Type: article
Abstract: The growth and characterization of superconducting thin films is essential for fundamental understanding and also for the use of these films in technological applications. In the present study, Ti 40 V 60 alloy thin films have been deposited using DC magnetron co-sputtering of Ti and V at ambient temperatures. The effect of deposition pressure on the film morphology, superconducting and normal state properties has been studied. Measurement of electrical resistance as a function of temperature indicates that up to a certain deposition pressure, the 20 nm thick Ti 40 V 60 films exhibit metallic behavior in the normal state and superconductivity at low temperatures. Beyond a threshold pressure, the films show a negative temperature coefficient of resistance with a residual resistance ratio less than one. Electrical transport measurements in the presence of magnetic field were performed to find the current–voltage ( I–V ) characteristics of the thin films. Analysis of the I–V curves indicates that the Ti 40 V 60 alloy thin films have a high transport critical current density ( J C ) e.g. 1.48 × 10 10 A m − 2 in zero magnetic field and 2.66 × 10 9 A m − 2 in 4 T (both at 4 K). Analysis of the field dependence of flux line pinning force density indicates a combined effect of core Δ k surface and core Δ k point pinning mechanisms (where k is the Ginzburg–Landau parameter). Additionally, spatial variations in the superconducting critical temperature ( T C ) across the sample contribute to δ T C pinning. In higher magnetic fields, a contribution from δl pinning (where l is the electron mean free path) also becomes significant. The findings indicate the potential of Ti 40 V 60 alloy thin film for superconducting device applications like cryogenic radiation detectors.
Authors: Shekhar Chandra Pandey, Shilpam Sharma, R Venkatesh, Ashish Khandelwal, L S Sharath Chandra, M K Chattopadhyay
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4415338214