Current Induced Resistive State in Fe(Se,Te) Superconducting Nanostrips.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Superconductivity

Background:

• Fe(Se,Te) thin films are promising for superconductive and micro-electronics.
• Understanding transport properties in nanostrips is key for device applications.

Purpose of the Study:

• To analyze current-voltage characteristics of Fe(Se,Te) nanostrips.
• To investigate magnetic flux line (vortex) pinning and creep flow.
• To assess the impact of self-generated magnetic fields on transport properties.

Main Methods:

• Fabrication of Fe(Se,Te) thin film nanostrips on CaF2 substrates.
• Measurement of current-voltage characteristics at various temperatures.
• Analysis using a modified classical creep flow model accounting for flux line interactions.

Main Results:

• Estimates for pinning potential (U) and range (δ) were derived.
• Observed voltages and critical current depression suggest low equilibrium flux lines and inhomogeneous current distribution.
• Sharp corners in nanostrip geometry facilitate magnetic flux line injection.

Conclusions:

• The classical creep flow model requires modifications for narrow superconducting strips.
• Fe(Se,Te) nanostrips exhibit unique flux pinning and creep behavior relevant to superconductive electronics.
• Geometric features significantly influence magnetic flux dynamics in these nanostructures.