Coherent Charge Transport in Ballistic InSb Nanowire Josephson Junctions.

Area of Science:

• Condensed Matter Physics
• Quantum Computing

Background:

• Hybrid superconductor-nanowire devices are key for exploring Majorana modes and topological quantum computation.
• Realizing ballistic, phase-coherent hybrid devices is essential for topological superconducting electronics.

Purpose of the Study:

• To investigate phase-coherent, ballistic charge transport in Josephson junction devices made from Indium Antimonide (InSb) nanowires.
• To assess the material quality of InSb nanowires grown by molecular-beam epitaxy for hybrid device applications.

Main Methods:

• Fabrication of Josephson junction devices using molecular-beam epitaxy grown InSb nanowires.
• Low-temperature transport measurements to study electrical properties.
• Analysis of gate-tunable supercurrent, multiple Andreev reflections, and critical current modulations.

Main Results:

• Clear evidence of phase-coherent, ballistic charge transport through InSb nanowires in Josephson junctions.
• Observation of gate-tunable proximity-induced supercurrent.
• Signatures of multiple Andreev reflections and Fabry-Pérot interference, confirming ballistic transport.

Conclusions:

• InSb nanowires grown by molecular-beam epitaxy exhibit excellent material quality.
• These hybrid superconducting devices are highly suitable for investigating topological states of matter and for topological quantum electronics.