Chiral Magnetic Josephson Junction as a Base for Low-Noise Superconducting Qubits

The lack of space inversion symmetry endows non-centrosymmetric superconducting materials with various interesting parity-breaking phenomena, including the anomalous Josephson effect. Our paper considers a Josephson junction of two non-centrosymmetric superconductors connected by a uniaxial ferromagnet. We show that this Chiral Magnetic Josephson junction (CMJ junction) exhibits a direct analog of the Chiral Magnetic Effect, which has already been observed in Weyl and Dirac semimetals. We suggest that the CMJ can serve as an element of a qubit with a Hamiltonian tunable by the ferromagnet's magnetization. The CMJ junction avoids using an offset magnetic flux in inductively shunted qubits, thus enabling a simpler and more robust architecture. Furthermore, when the uniaxial ferromagnet's easy axis is directed across the junction, the resulting chiral magnetic qubit provides robust protection from the noise caused by magnetization fluctuations.

Automated summary

Our paper explores the Chiral Magnetic Josephson junction (CMJ junction) composed of two non-centrosymmetric superconductors connected by a uniaxial ferromagnet. This structure shows an analog of the Chiral Magnetic Effect and has potential applications as a qubit with a tunable Hamiltonian. The CMJ junction offers a simpler and more robust architecture without the need for an offset magnetic flux, providing strong protection against noise from magnetization fluctuations.