Abstract: A method to evaluate a semiconductor-superconductor heterojunction for use in a qubit register of a topological quantum computer includes (a) measuring one or both of a radio-frequency (RF) junction admittance of the semiconductor-superconductor heterojunction and a sub-RF conductance including a non-local conductance of the semiconductor-superconductor heterojunction, to obtain mapping data and refinement data; (b) finding by analysis of the mapping data one or more regions of a parameter space consistent with an unbroken topological phase of the semiconductor-superconductor heterojunction; and (c) finding by analysis of the refinement data a boundary of the unbroken topological phase in the parameter space and a topological gap of the semiconductor-superconductor heterojunction for at least one of the one or more regions of the parameter space.

Abstract: A method to evaluate a semiconductor-superconductor heterojunction for use in a qubit register of a topological quantum computer includes measuring a radio-frequency (RF) junction admittance of the semiconductor-superconductor heterojunction to obtain mapping data; finding by analysis of the mapping data one or more regions of a parameter space consistent with an unbroken topological phase of the semiconductor-superconductor heterojunction; measuring a sub-RF conductance including a non-local conductance of the semiconductor-superconductor heterojunction in each of the one or more regions of the parameter space, to obtain refinement data; and finding by analysis of the refinement data a boundary of the unbroken topological phase in the parameter space and a topological gap of the semiconductor-superconductor heterojunction for at least one of the one or more regions of the parameter space.

Abstract: A method to evaluate a semiconductor-superconductor heterojunction for use in a qubit register of a topological quantum computer includes measuring a radio-frequency (RF) junction admittance of the semiconductor-superconductor heterojunction to obtain mapping data; finding by analysis of the mapping data one or more regions of a parameter space consistent with an unbroken topological phase of the semiconductor-superconductor heterojunction; measuring a sub-RF conductance including a non-local conductance of the semiconductor-superconductor heterojunction in each of the one or more regions of the parameter space, to obtain refinement data; and finding by analysis of the refinement data a boundary of the unbroken topological phase in the parameter space and a topological gap of the semiconductor-superconductor heterojunction for at least one of the one or more regions of the parameter space.

Abstract: The disclosure relates to a quantum device and method of fabricating the same. The device comprises one or more semiconductor-superconductor nanowires, each comprising a length of semiconductor material and a coating of superconductor material coated on the semiconductor material. The nanowires may be formed over a substrate. In a first aspect at least some of the nanowires are full-shell nanowires with superconductor material being coated around a full perimeter of the semiconductor material along some or all of the length of the wire, wherein the device is operable to induce at least one Majorana zero mode, MZM, in one or more active ones of the full-shell nanowires. In a second aspect at least some of the nanowires are arranged vertically relative to the plane of the substrate in the finished device.

Abstract: The disclosure relates to a quantum device and method of fabricating the same. The device comprises one or more semiconductor-superconductor nanowires, each comprising a length of semiconductor material and a coating of superconductor material coated on the semiconductor material. The nanowires may be formed over a substrate. In a first aspect at least some of the nanowires are full-shell nanowires with superconductor material being coated around a full perimeter of the semiconductor material along some or all of the length of the wire, wherein the device is operable to induce at least one Majorana zero mode, MZM, in one or more active ones of the full-shell nanowires. In a second aspect at least some of the nanowires are arranged vertically relative to the plane of the substrate in the finished device.

Abstract: The disclosure relates to a quantum device and method of fabricating the same. The device comprises one or more semiconductor-superconductor nanowires, each comprising a length of semiconductor material and a coating of superconductor material coated on the semiconductor material. The nanowires may be formed over a substrate. In a first aspect at least some of the nanowires are full-shell nanowires with superconductor material being coated around a full perimeter of the semiconductor material along some or all of the length of the wire, wherein the device is operable to induce at least one Majorana zero mode, MZM, in one or more active ones of the full-shell nanowires. In a second aspect at least some of the nanowires are arranged vertically relative to the plane of the substrate in the finished device.

Abstract: The disclosure relates to a quantum device and method of fabricating the same. The device comprises one or more semiconductor-superconductor nanowires, each comprising a length of semiconductor material and a coating of superconductor material coated on the semiconductor material. The nanowires may be formed over a substrate. In a first aspect at least some of the nanowires are full-shell nanowires with superconductor material being coated around a full perimeter of the semiconductor material along some or all of the length of the wire, wherein the device is operable to induce at least one Majorana zero mode, MZM, in one or more active ones of the full-shell nanowires. In a second aspect at least some of the nanowires are arranged vertically relative to the plane of the substrate in the finished device.