Ultracompact fiber integrated X-ray dosimeter based on scintillators coupled to a nano-optical antenna

TL;DR

This paper introduces an ultracompact, fiber-integrated X-ray dosimeter using nano-optical antennas and scintillators, enabling high-resolution, real-time X-ray detection suitable for endoscopic applications.

Contribution

It presents the first experimental implementation of a fiber-based X-ray dosimeter with nano-optical antenna coupling for enhanced sensitivity and spatial resolution.

Findings

Achieved micron-scale spatial resolution in X-ray profiling.

Demonstrated real-time dosimetry with high sensitivity at 8-10 keV.

Developed a plug-and-play, flexible fiber-based X-ray sensor.

Abstract

High energy radiations are nowadays cornerstone in scientific, medical and industrial imaging and cancer therapy. However, their detection and dosimetry are restricted to systems of modest compactness that are not compatible with endoscopy. Here, we report the first experimental imaging and dosimetry of X-rays with an ultracompact sensor integrated at the end of a single mode optical fiber (125 $\mu$m full diameter). We realize such a dosimeter by coupling luminescent scintillators to a nano-optical antenna engineered at the end of the fiber and by detecting in-fiber outcoupled luminescence with a photon counter. Direct profile and real-time dosimetry of a X-ray focused beam reveals a spatial resolution of a few microns together with a sensitivity better than 10$^3$ X-photons$/$s$/\mu$m$^2$ at energies of 8-10 keV. Because the nano-optical platform is auto-aligned with respect to the fiber, the resulting dosimeter is plug-and-play, flexible, and it is suitable for ultralow footprint endoscopic investigations at higher X-ray energies. Our nano-optical approach thus offers the possibility of X-ray profiling and dosimetry in ultra-confined environments, opening up new avenues in the fields of X-ray imaging, real-time control of cancer radiotherapies and Curie therapies, medical and industrial endoscopy, etc. With this study, nano-optical antennas make a first key contribution to the development of X-ray sensing protocols and architectures.