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Selective control of conductance modes in multi-terminal Josephson junctions.

ABSTRACT: The Andreev bound state spectra of multi-terminal Josephson junctions form an artificial band structure, which is predicted to host tunable topological phases under certain conditions. However, the number of conductance modes between the terminals of a multi-terminal Josephson junction must be few in order for this spectrum to be experimentally accessible. In this work, we employ a quantum point contact geometry in three-terminal Josephson devices to demonstrate independent control of conductance modes between each pair of terminals and access to the single-mode regime coexistent with the presence of superconducting coupling. These results establish a full platform on which to realize tunable Andreev bound state spectra in multi-terminal Josephson junctions.

SUBMITTER: Graziano GV

PROVIDER: S-EPMC9547902 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Selective control of conductance modes in multi-terminal Josephson junctions.

Graziano Gino V GV Gupta Mohit M Pendharkar Mihir M Dong Jason T JT Dempsey Connor P CP Palmstrøm Chris C Pribiag Vlad S VS

Nature communications 20221008 1

The Andreev bound state spectra of multi-terminal Josephson junctions form an artificial band structure, which is predicted to host tunable topological phases under certain conditions. However, the number of conductance modes between the terminals of a multi-terminal Josephson junction must be few in order for this spectrum to be experimentally accessible. In this work, we employ a quantum point contact geometry in three-terminal Josephson devices to demonstrate independent control of conductanc ...[more]

PMID: 36209199

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