An all-epitaxial nitride heterostructure with concurrent quantum Hall effect and superconductivity

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Computing

Background:

• Achieving simultaneous quantum Hall effect and superconductivity is crucial for topological quantum computing.
• Conflicting magnetic field requirements have historically hindered the integration of these two topological phases.
• Nitride-based materials offer potential for high-temperature superconductivity and robust electronic properties.

Purpose of the Study:

• To develop seamless heterostructures integrating superconductivity and the quantum Hall effect.
• To overcome the incompatibility of magnetic field requirements for these two topological phases.
• To establish an industrially viable platform for robust quantum devices.

Main Methods:

• Epitaxial growth of a high critical temperature nitride superconductor.
• Fabrication of a subsequent nitride semiconductor heterostructure with controlled metal polarity.
• Magnetotransport measurements of spatially separated 2D electron gas and superconducting layers.

Main Results:

• Observation of a clean integer quantum Hall effect in a polarization-induced 2D electron gas within a high-electron mobility transistor.
• Identification of a narrow window of magnetic fields and temperatures where both quantum Hall and superconducting properties coexist.
• Demonstration that this coexistence window can be expanded in epitaxial nitride superconductor/semiconductor heterostructures.

Conclusions:

• Epitaxial nitride superconductor/semiconductor heterostructures provide a promising platform for integrating topological quantum phases.
• The developed heterostructures enable the exploitation of topologically protected transport for advanced quantum devices.
• This work paves the way for industrially viable quantum electronics.