Quantum computing with graphene plasmons
Abstract
Among the various approaches to quantum computing, all-optical architectures are especially promising due to the robustness and mobility of single photons. However, the creation of the two-photon quantum logic gates required for universal quantum computing remains a challenge. Here we propose a universal two-qubit quantum logic gate, where qubits are encoded in surface plasmons in graphene nanostructures, that exploits graphene's strong third-order nonlinearity and long plasmon lifetimes to enable single-photon-level interactions. In particular, we utilize strong two-plasmon absorption in graphene nanoribbons, which can greatly exceed single-plasmon absorption to create a “square-root-of-swap” that is protected by the quantum Zeno effect against evolution into undesired failure modes. Our gate does not require any cryogenic or vacuum technology, has a footprint of a few hundred nanometers, and reaches fidelities and success rates well above the fault-tolerance threshold, suggesting that graphene plasmonics offers a route towards scalable quantum technologies.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 02, 2019
- Source ID
- 10.1038/s41534-019-0150-2
Entities
People
- F. Javier García de Abajo
- Irati Alonso Calafell
- J. D. Cox
- J. R. M. Saavedra
- L. A. Rozema
- Milan Radonjić
- Philip Walther
Organizations
- Austrian Research Promotion Agency
- Austrian Science Fund
- European Commission
- Fundación Cellex
- John Templeton Foundation
- United States Air Force