Patent · US Expired

Qubit using a Josephson junction between s-wave and d-wave superconductors

US6459097B1 · kind B1 · utility

83Cited by
7References
25Claims
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Assignee

Inventor

Key dates

Filing dateJan 7, 2000
Grant dateOct 1, 2002
Priority date
Expiry dateJan 7, 2020

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S977/933
  • WIPO fieldMicro-structural and nano-technology
  • WIPO sectorChemistry

Abstract

A solid-state quantum computing structure includes a set of islands that Josephson junctions separate from a first superconducting bank. A d-wave superconductor is on one side of the Josephson junctions (either the islands' side or the bank's side), and an s-wave superconductor forms the other side of the Josephson junctions. The d-wave superconductor causes the ground state for the supercurrent at each junction to be doubly degenerate, with two supercurrent ground states having distinct magnetic moments. These quantum states of the supercurrents at the junctions create qubits for quantum computing. The quantum states can be uniformly initialized from the bank, and the crystal orientations of the islands relative to the bank influence the initial quantum state and tunneling probabilities between the ground states. A second bank, which a Josephson junction separates from the first bank, can be coupled to the islands through single electron transistors for selectably initializing one or more of the supercurrents in a different quantum state. Single electron transistors can also be between the islands to control entanglements while the quantum states evolve. After the quantum states h…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.