Abstract: A finger SQUID qubit device and method for performing quantum computation with said device is disclosed. A finger SQUID qubit device includes a superconducting loop and one or more superconducting fingers, wherein the fingers extend to the interior of said loop. Each finger has a mesoscopic island at the tip, separated from the rest of the finger by a Josephson junction. A system for performing quantum computation with the finger SQUID qubit device includes a mechanism for initializing, entangling, and reading out the qubits. The mechanism may involve passing a bias current across the leads of the superconducting loop and a mechanism for measuring a potential change across the leads of the superconducting loop. Furthermore, a control system includes a mechanism for addressing specific qubits in a quantum register of finger SQUID devices.

Abstract: A finger SQUID qubit device and method for performing quantum computation with said device is disclosed. A finger SQUID qubit device includes a superconducting loop and one or more superconducting fingers, wherein the fingers extend to the interior of said loop. Each finger has a mesoscopic island at the tip, separated from the rest of the finger by a Josephson junction. A system for performing quantum computation with the finger SQUID qubit device includes a mechanism for initializing, entangling, and reading out the qubits. The mechanism may involve passing a bias current across the leads of the superconducting loop and a mechanism for measuring a potential change across the leads of the superconducting loop. Furthermore, a control system includes a mechanism for addressing specific qubits in a quantum register of finger SQUID devices.

Abstract: A finger SQUID qubit device and method for performing quantum computation with said device is disclosed. A finger SQUID qubit device includes a superconducting loop and one or more superconducting fingers, wherein the fingers extend to the interior of said loop. Each finger has a mesoscopic island at the tip, separated from the rest of the finger by a Josephson junction. A system for performing quantum computation with the finger SQUID qubit device includes a mechanism for initializing, entangling, and reading out the qubits. The mechanism may involve passing a bias current across the leads of the superconducting loop and a mechanism for measuring a potential change across the leads of the superconducting loop. Furthermore, a control system includes a mechanism for addressing specific qubits in a quantum register of finger SQUID devices.

Abstract: A finger SQUID qubit device and method for performing quantum computation with said device is disclosed. A finger SQUID qubit device includes a superconducting loop and one or more superconducting fingers, wherein the fingers extend to the interior of said loop. Each finger has a mesoscopic island at the tip, separated from the rest of the finger by a Josephson junction. A system for performing quantum computation with the finger SQUID qubit device includes a mechanism for initializing, entangling, and reading out the qubits. The mechanism may involve passing a bias current across the leads of the superconducting loop and a mechanism for measuring a potential change across the leads of the superconducting loop. Furthermore, a control system includes a mechanism for addressing specific qubits in a quantum register of finger SQUID devices.

Abstract: A finger SQUID qubit device and method for performing quantum computation with said device is disclosed. A finger SQUID qubit device includes a superconducting loop and one or more superconducting fingers, wherein the fingers extend to the interior of said loop. Each finger has a mesoscopic island at the tip, separated from the rest of the finger by a Josephson junction. A system for performing quantum computation with the finger SQUID qubit device includes a mechanism for initializing, entangling, and reading out the qubits. The mechanism may involve passing a bias current across the leads of the superconducting loop and a mechanism for measuring a potential change across the leads of the superconducting loop. Furthermore, a control system includes a mechanism for addressing specific qubits in a quantum register of finger SQUID devices.

Abstract: A finger SQUID qubit device and method for performing quantum computation with said device is disclosed. A finger SQUID qubit device includes a superconducting loop and one or more superconducting fingers, wherein the fingers extend to the interior of said loop. Each finger has a mesoscopic island at the tip, separated from the rest of the finger by a Josephson junction. A system for performing quantum computation with the finger SQUID qubit device includes a mechanism for initializing, entangling, and reading out the qubits. The mechanism may involve passing a bias current across the leads of the superconducting loop and a mechanism for measuring a potential change across the leads of the superconducting loop. Furthermore, a control system includes a mechanism for addressing specific qubits in a quantum register of finger SQUID devices.

Abstract: A finger SQUID qubit device and method for performing quantum computation with said device is disclosed. A finger SQUID qubit device includes a superconducting loop and one or more superconducting fingers, wherein the fingers extend to the interior of said loop. Each finger has a mesoscopic island at the tip, separated from the rest of the finger by a Josephson junction. A system for performing quantum computation with the finger SQUID qubit device includes a mechanism for initializing, entangling, and reading out the qubits. The mechanism may involve passing a bias current across the leads of the superconducting loop and a mechanism for measuring a potential change across the leads of the superconducting loop. Furthermore, a control system includes a mechanism for addressing specific qubits in a quantum register of finger SQUID devices.

Abstract: A finger SQUID qubit device and method for performing quantum computation with said device is disclosed. A finger SQUID qubit device includes a superconducting loop and one or more superconducting fingers, wherein the fingers extend to the interior of said loop. Each finger has a mesoscopic island at the tip, separated from the rest of the finger by a Josephson junction. A system for performing quantum computation with the finger SQUID qubit device includes a mechanism for initializing, entangling, and reading out the qubits. The mechanism may involve passing a bias current across the leads of the superconducting loop and a mechanism for measuring a potential change across the leads of the superconducting loop. Furthermore, a control system includes a mechanism for addressing specific qubits in a quantum register of finger SQUID devices.

Abstract: In accordance with embodiments of the present invention, a junction of an unconventional superconductor, an intermediate material, and a conventional superconducting material is presented. In some embodiments, the resulting junction is in the c-axis direction of the orthorhombic unconventional superconductor. Alternatively, the junction is in the a-b plane direction. Interface junctions according to embodiments of the present invention may be used in super low inductance qubits (SLIQs) and in permanent readout superconducting qubits (PRSQs), can form the basis of quantum registers, and can allow for parity keys or other devices made from conventional superconducting material to be attached to qubits made from unconventional superconducting material or vice versa. Coherent tunnel junctions according to embodiments of the present invention may be used to form parity keys or coherently couple two regions of a superconducting material.