Trap-Controlled Conduction and Metal-Insulator Transition in Superconducting Cuprate Memristors

Area of Science:

• Materials Science
• Condensed Matter Physics
• Neuroscience

Background:

• Memristive devices are crucial for neuromorphic computing.
• Understanding resistive switching mechanisms in high-temperature superconducting cuprates is essential.
• Yttrium barium copper oxide (YBCO) is a promising material for these devices.

Purpose of the Study:

• Investigate the microscopic mechanisms of resistive switching in YBCO memristors.
• Explore the temperature dependence of memristor behavior from 80-300 K.
• Elucidate the role of interfacial layers and trap dynamics in device operation.

Main Methods:

• Fabrication and characterization of YBCO memristors.
• Temperature-dependent current-voltage (I-V) measurements.
• Analysis of conduction mechanisms and trap state dynamics.

Main Results:

• Observed robust bipolar switching in YBCO memristors across the studied temperature range.
• Identified temperature-independent SET and RESET voltages.
• Demonstrated trap-controlled space-charge-limited conduction modulated by shallow and deep traps at an oxygen-deficient interface.
• Revealed the formation of a deoxygenated interfacial layer enabling electrostatic control over a field-induced metal-insulator transition.

Conclusions:

• Proposed a dual-trap model involving CuO chain fragmentation to explain nonvolatile switching.
• Highlighted the critical role of dynamic trap states in cuprate memristor functionality.
• Indicated the potential of these memristors for cryogenic neuromorphic computing platforms integrated with superconducting circuits.