Encoding classical data into the squeezing of noisy-states for plasmonic communication

TL;DR

This paper introduces a novel plasmonic communication method that encodes information into the nonclassicality of surface plasmon polaritons, enabling robust, long-distance, high-bandwidth data transfer even in noisy, thermal environments.

Contribution

It presents a new paradigm for plasmonic communication by encoding data into nonclassicality, demonstrating enhanced information retrieval from noisy states over long distances.

Findings

Encoding into nonclassicality enables long-distance communication.

Information remains accessible after propagation with few measurements.

Thermal background can be exploited for robust nanoscale communication.

Abstract

Surface plasmon polaritons (SPPs) are known to preserve quantum optical properties --such as squeezing-- over distances far exceeding those of classical field amplitudes. However, the surviving squeezing typically becomes so weak that its detection requires prohibitively large numbers of measurements. Here we introduce a fundamentally new paradigm for plasmonic communication in which nonclassicality itself carries the information. We (i) encode classical data (bits or dits) directly into the {\it degree of nonclassicality} (e.g., squeezing) of SPPs, thereby enabling information transfer over distances where classical amplitude encoding fails. We further (ii) show that this information can be retrieved from long-lived correlations generated at the readout stage via a beam splitter. Crucially, we demonstrate that (iii) encoding on initially noisy states leads to a counterintuitive enhancement: the encoded information remains accessible after long propagation distances using only a few measurements, outperforming both squeezed vacuum and amplitude-based schemes by orders of magnitude. Finally, (iv) in the THz regime --relevant for graphene and carbon-nanotube platforms at room temperature-- we \textit{exploit}, rather than suppress, the intrinsic thermal background, enabling robust, high-bandwidth nanoscale communication.