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arXiv · 2207.05122

Nonlinear quantum logic with colliding graphene plasmons

Giuseppe Calajò·Philipp K. Jenke·Lee A. Rozema·Philip Walther·Darrick E. Chang·Joel D. Cox
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Abstract

Graphene has emerged as a promising platform to bring nonlinear quantum optics to the nanoscale, where a large intrinsic optical nonlinearity enables long-lived and actively tunable plasmon polaritons to strongly interact. Here we theoretically study the collision between two counter-propagating plasmons in a graphene nanoribbon, where transversal subwavelength confinement endows propagating plasmons with %large effective masses a flat band dispersion that enhances their interaction. This scenario presents interesting possibilities towards the implementation of multi-mode polaritonic gates that circumvent limitations imposed by the Shapiro no-go theorem for photonic gates in nonlinear optical fibers. As a paradigmatic example we demonstrate the feasibility of a high fidelity conditional Pi phase shift (CZ), where the gate performance is fundamentally limited only by the single-plasmon lifetime. These results open new exciting avenues towards quantum information and many-body applications with strongly-interacting polaritons.

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Giuseppe Calajò, Philipp K. Jenke, Lee A. Rozema, Philip Walther, Darrick E. Chang, Joel D. Cox. 2022-07-11. Nonlinear quantum logic with colliding graphene plasmons. https://doi.org/10.1103/physrevresearch.5.013188

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