Tuning the superconducting performance of YBa₂Cu₃O_7-δ films through field-induced oxygen doping

Area of Science:

• Materials Science
• Condensed Matter Physics
• Superconductivity

Background:

• Metal-insulator transitions and resistive switching are key phenomena in materials science.
• Resistive switching in oxides is often linked to oxygen vacancies, but mechanisms remain unclear.
• Cuprate superconductors like YBa2Cu3O7-δ (YBCO) exhibit complex behaviors under electrical stress.

Purpose of the Study:

• To investigate field-induced oxygen diffusion in YBCO devices.
• To analyze the impact of resistive switching on superconducting properties, specifically critical current density.
• To identify the role of induced defects in device performance.

Main Methods:

• Utilized gate voltage pulses to switch YBCO devices to different resistive states.
• Measured magnetic field and angular dependence of critical current density.
• Employed transition electron microscopy to analyze structural changes.

Main Results:

• Field-induced resistive switching to high resistance states involves the generation of YBa2Cu4O7 (Y124) intergrowths.
• These intergrowths are associated with a significant number of oxygen vacancies.
• Observed changes in critical current density align with the structural modifications.

Conclusions:

• Field-induced oxygen doping significantly impacts cuprate superconductor performance.
• The generation of Y124 intergrowths is a key mechanism in field-induced resistive switching.
• Understanding these mechanisms is crucial for developing advanced superconducting devices.