Quantum random number generation using an on-chip plasmonic beamsplitter

TL;DR

This paper demonstrates a compact on-chip quantum random number generator using a plasmonic beamsplitter, converting single photons into surface plasmons to generate high-rate, high-quality random bits suitable for quantum technologies.

Contribution

It introduces a novel on-chip plasmonic device for quantum random number generation, achieving high speed and quality in a compact form factor.

Findings

Achieved a random number generation rate of 2.37 Mbits/s.

Generated random sequences comparable in quality to other quantum photonic devices.

Demonstrated the device's suitability for integration in quantum computing and communication.

Abstract

We report an experimental realisation of a quantum random number generator using a plasmonic beamsplitter. Free-space single photons are converted into propagating single surface plasmon polaritons on a gold stripe waveguide via a grating. The surface plasmons are then guided to a region where they are scattered into one of two possible outputs. The presence of a plasmonic excitation in a given output determines the value of a random bit generated from the quantum scattering process. Using a stream of single surface plasmons injected into the beamsplitter we achieve a quantum random number generation rate of 2.37 Mbits/s even in the presence of loss. We characterise the quality of the random number sequence generated, finding it to be comparable to sequences from other quantum photonic-based devices. The compact nature of our nanophotonic device makes it suitable for tight integration in on-chip applications, such as in quantum computing and communication schemes.