Abstract: A superconducting structure that can operate, for example, as a qubit or a superconducting switch is presented. The structure includes a loop formed from two parts. A first part includes two superconducting materials separated by a junction. The junction can, for example, be a 45° grain boundary junction. The second part can couple the two superconducting materials across the junction. The second part includes a superconducting material coupled to each of the two superconducting materials of the first part through c-axis junctions. Further embodiments of the invention can be as a coherent unconventional superconducting switch, or a variable phase shift unconventional superconductor junction device.

Abstract: The present invention comprises a junction between an unconventional superconductor, an intermediate material, and a conventional superconducting material. In some embodiments, the unconventional superconductor has an orthorhombic crystal structure and the supercurrent in the resulting junction flows in the c-axis direction of the orthorhombic crystal. In other embodiments, the supercurrent flows parallel to a direction in the a-b plane. Interface junctions according to embodiments of the present invention may be used in superconducting low inductance qubits (SLIQs) and in permanent readout superconducting qubits (PRSQs), can form the basis of quantum registers, and can permit parity keys or other devices made from conventional superconducting material to be attached to qubits made from unconventional superconducting material or vice versa.

Abstract: A superconducting structure that can operate, for example, as a qubit or a superconducting switch is presented. The structure includes a loop formed from two parts. A first part includes two superconducting materials separated by a junction. The junction can, for example, be a 45° grain boundary junction. The second part can couple the two superconducting materials across the junction. The second part includes a superconducting material coupled to each of the two superconducting materials of the first part through c-axis junctions. Further embodiments of the invention can be as a coherent unconventional superconducting switch, or a variable phase shift unconventional superconductor junction device.

Abstract: The present invention comprises a junction between an unconventional superconductor, an intermediate material, and a conventional superconducting material. In some embodiments, the unconventional superconductor has an orthorhombic crystal structure and the supercurrent in the resulting junction flows in the c-axis direction of the orthorhombic crystal. In other embodiments, the supercurrent flows parallel to a direction in the a-b plane. Interface junctions according to embodiments of the present invention may be used in superconducting low inductance qubits (SLIQs) and in permanent readout superconducting qubits (PRSQs), can form the basis of quantum registers, and can permit parity keys or other devices made from conventional superconducting material to be attached to qubits made from unconventional superconducting material or vice versa.