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arXiv · 2303.05951

Half-integer Shapiro steps in highly transmissive InSb nanoflag Josephson junctions

Andrea Iorio·Alessandro Crippa·Bianca Turini·Sedighe Salimian·Matteo Carrega·Luca Chirolli·Valentina Zannier·Lucia Sorba·Elia Strambini·Francesco Giazotto·Stefan Heun
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Abstract

We investigate a ballistic InSb nanoflag-based Josephson junction with Nb superconducting contacts. The high transparency of the superconductor-semiconductor interfaces enables the exploration of quantum transport with parallel short and long conducting channels. Under microwave irradiation, we observe half-integer Shapiro steps that are robust to temperature, suggesting their possible non-equilibrium origin. Our results demonstrate the potential of ballistic InSb nanoflags Josephson junctions as a valuable platform for understanding the physics of hybrid devices and investigating their non-equilibrium dynamics.

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Andrea Iorio, Alessandro Crippa, Bianca Turini, Sedighe Salimian, Matteo Carrega, Luca Chirolli, Valentina Zannier, Lucia Sorba, Elia Strambini, Francesco Giazotto, Stefan Heun. 2023-03-10. Half-integer Shapiro steps in highly transmissive InSb nanoflag Josephson junctions. https://doi.org/10.1103/physrevresearch.5.033015

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