Reentrant Resistive Behavior and Dimensional Crossover in Disordered Superconducting TiN Films

Area of Science:

• Condensed Matter Physics
• Materials Science
• Superconductivity

Background:

• Reentrant, N-shaped temperature dependence of normal state resistance is common in disordered superconductors near the superconductor-to-insulator transition.
• The origin of this ubiquitous phenomenon in materials like cuprates and thin films remains debated.

Purpose of the Study:

• To investigate the universality of reentrant behavior in strongly disordered superconducting titanium nitride (TiN) films.
• To provide a quantitative description of the N-shaped resistance curve.

Main Methods:

• Experimental investigation of strongly disordered superconducting TiN films.
• Analysis of the normal state resistance as a function of temperature.

Main Results:

• Demonstrated universality of reentrant behavior in TiN films.
• Quantitatively described the N-shaped resistance curve, showing a linear decrease upon cooling followed by a minimum.
• Identified the minimum as a signature of a 3D-2D dimensional crossover.
• Observed resistance increase in the 2D regime due to quantum effects before dropping to zero in the superconducting state.

Conclusions:

• Disorder plays a crucial role in dimensional crossover effects in superconductors.
• The study provides a comprehensive understanding of the reentrant resistance phenomenon in disordered systems.