Thermal Properties of the Superconductor-Quantum Hall Interface

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Phenomena

Background:

• Combining superconductors (SC) with the quantum Hall (QH) effect is crucial for engineering topological states.
• Research has primarily focused on electronic properties, neglecting thermal responses at these interfaces.
• Understanding thermal transport is essential for characterizing novel quantum states.

Purpose of the Study:

• To investigate the thermal properties at the interface between type-II superconducting electrodes and graphene in the QH regime.
• To probe the local electron temperature within the superconductor near the biased interface.
• To elucidate the mechanisms behind thermal transport in this hybrid system.

Main Methods:

• Utilizing thermal noise measurements to determine the local electron temperature.
• Examining the interface between type-II superconductors and graphene under quantum Hall conditions.
• Analyzing the temperature dependence of thermal conductivity.

Main Results:

• A surprising and significant thermal conductivity was observed in the superconductor, linear with temperature.
• This indicates electronic heat transport, contrary to expectations due to suppressed quasiparticles.
• The findings suggest the involvement of normal states within vortex cores.

Conclusions:

• Superconductors can exhibit substantial electronic heat transport even in proximity to quantum Hall states.
• The observed thermal conductivity is likely mediated by the overlap of normal states in vortex cores.
• This highlights the importance of considering thermal properties in hybrid SC-QH systems.