Loopless multiterminal quantum circuits at odd parity

• URL: http://arxiv.org/abs/2601.13369v1
• Date: Mon, 19 Jan 2026 20:07:27 GMT
• Title: Loopless multiterminal quantum circuits at odd parity
• Authors: Antonio Manesco, Anton Akhmerov, Valla Fatemi,
• Abstract summary: We investigate loopless multiterminal hybrid superconducting devices at odd fermion parity with time-reversal symmetry.<n>We find that the energy-phase relationship has a double minimum corresponding to opposite windings of the superconducting phases.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: We theoretically investigate loopless multiterminal hybrid superconducting devices at odd fermion parity with time-reversal symmetry. We find that the energy-phase relationship has a double minimum corresponding to opposite windings of the superconducting phases. Spin-orbit coupling adds multi-axial spin splittings, which contrasts with two-terminal devices where spin dependence is uniaxial. Capacitive shunting localizes quantum circuit states in the wells and exponentially suppresses their splitting. For weak spin-orbit strength, the system has a four-dimensional spin-chirality low-energy subspace which can be universally controlled with electric fields only.

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