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Supercurrent and multiple Andreev reflections in an InSb nanowire Josephson junction
H A Nilsson1, P Samuelsson, P Caroff
1Division of Solid State Physics, Lund University, P.O. Box 118, S-221 00 Lund, Sweden.
Nano Letters
|December 7, 2011
Summary
High-quality indium antimonide (InSb) nanowires demonstrate tunable supercurrents in Josephson junction devices. This research highlights InSb nanowires as a promising platform for exploring novel quantum phenomena, including Majorana fermions.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanoelectronics
Background:
- Indium antimonide (InSb) nanowires are advanced semiconductor materials.
- They are crucial for developing high-performance nanoelectronics and quantum devices.
- InSb nanowires are also vital for studying novel solid-state physics phenomena.
Purpose of the Study:
- To investigate superconductivity in epitaxially grown InSb nanowires.
- To fabricate and characterize superconductor-normal conductor-superconductor (S-N-S) Josephson junction devices using InSb nanowires.
- To explore the potential of InSb nanowires for realizing exotic quantum phenomena like Majorana fermions.
Main Methods:
- Fabrication of an S-N-S junction device using an InSb nanowire with aluminum-based superconducting contacts.
- Measurement of proximity-induced supercurrent in the InSb nanowire.
- Characterization of critical current tunability via gating and analysis of multiple Andreev reflection (MAR) characteristics.
Main Results:
- Demonstration of a tunable proximity-induced supercurrent in the InSb nanowire segment.
- Observation of multiple Andreev reflection (MAR) characteristics in the voltage bias configuration.
- Detailed study of the temperature and magnetic field dependence of critical current and MAR features, including excess current analysis.
Conclusions:
- Epitaxially grown InSb nanowires exhibit robust superconducting properties.
- The InSb nanowire-based Josephson junction is a viable platform for tunable superconductivity.
- InSb nanowires are a promising material system for the experimental realization and study of Majorana fermions and other novel quantum phenomena.
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