Electrical control of a solid-state flying qubit

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Nature Nanotechnology – Electrical control of a solid-state flying qubit

Solid-state approaches to quantum information technology are attractive because they are scalable. The coherent transport of quantum information over large distances is a requirement for any practical quantum computer and has been demonstrated by coupling super-conducting qubits to photons1. Single electrons have also been transferred between distant quantum dots in times shorter than their spin coherence time. However, until now, there have been no demonstrations of scalable ‘flying qubit’ architectures—systems in which it is possible to perform quantum operations on qubits while they are being coherently transferred—in solid-state systems. These architectures allow for control over qubit separation and for non-local entanglement, which makes them more amenable to integration and scaling than static qubit approaches. Here, we report the transport and manipulation of qubits over distances of 6 micron within 40 ps, in an Aharonov–Bohm ring connected to two-channel wires that have a tunable tunnel coupling between channels. The flying qubit state is defined by the presence of a travelling electron in either channel of the wire, and can be controlled without a magnetic field. Our device has shorter quantum gates (less than 1 micron), longer coherence lengths (~86 micron at 70 mK) and higher operating frequencies (~100 GHz) than other solid-state implementations of flying qubit

Device image and observed conventional AB oscillation

Nextbigfuture had reported on progress to solid state diamond qubits.

Experimental setup used in measurements.

10 pages of supplemental information

If you liked this article, please give it a quick review on ycombinator or StumbleUpon. Thanks

Electrical control of a solid-state flying qubit

by

Nature Nanotechnology – Electrical control of a solid-state flying qubit

Solid-state approaches to quantum information technology are attractive because they are scalable. The coherent transport of quantum information over large distances is a requirement for any practical quantum computer and has been demonstrated by coupling super-conducting qubits to photons1. Single electrons have also been transferred between distant quantum dots in times shorter than their spin coherence time. However, until now, there have been no demonstrations of scalable ‘flying qubit’ architectures—systems in which it is possible to perform quantum operations on qubits while they are being coherently transferred—in solid-state systems. These architectures allow for control over qubit separation and for non-local entanglement, which makes them more amenable to integration and scaling than static qubit approaches. Here, we report the transport and manipulation of qubits over distances of 6 micron within 40 ps, in an Aharonov–Bohm ring connected to two-channel wires that have a tunable tunnel coupling between channels. The flying qubit state is defined by the presence of a travelling electron in either channel of the wire, and can be controlled without a magnetic field. Our device has shorter quantum gates (less than 1 micron), longer coherence lengths (~86 micron at 70 mK) and higher operating frequencies (~100 GHz) than other solid-state implementations of flying qubit

Device image and observed conventional AB oscillation

Nextbigfuture had reported on progress to solid state diamond qubits.

Experimental setup used in measurements.

10 pages of supplemental information

If you liked this article, please give it a quick review on ycombinator or StumbleUpon. Thanks