Controlling X-ray emission with dispersion-engineered surface plasmon polaritons

TL;DR

This paper introduces a method to control the angular and spectral properties of hard x-ray emission by using dispersion-engineered surface plasmon polaritons on a nonlinear crystal, enabling tunable and designable x-ray sources.

Contribution

It presents a novel scheme for controlling x-ray emission through entanglement with engineered surface plasmon polaritons, extending surface-plasmon-assisted nonlinear and quantum x-ray optics.

Findings

Dispersion engineering reshapes phase-matching for x-ray emission.

Tunable angular-spectral structure imprinted on x-ray photons.

Enables compact, designable control of x-ray sources.

Abstract

We propose controlling the angular and spectral distribution of hard x-ray emission by entangling x-ray photons with ultraviolet surface plasmon polaritons (SPPs) whose dispersion is engineered by a metal-dielectric multilayer on a nonlinear crystal. Spontaneous parametric down-conversion of an x-ray pump produces a hard x-ray signal photon correlated with an ultraviolet SPP mode near its resonance. Engineering the SPPs dispersion reshapes the phase-matching landscape and imprints tunable angular-spectral structure on the emitted x-ray photons. The scheme enables compact, designable control of x-ray emission and extends surface-plasmon-assisted nonlinear and quantum x-ray optics.