Single-photon counting pixel detector for soft X-rays
Abstract
Soft X-ray experiments at synchrotron light sources are essential for a wide range of research fields. However, commercially available detectors for this energy range often cannot deliver the necessary combination of quantum efficiency, signal-to-noise ratio, dynamic range, speed, and radiation hardness within a single system. While hybrid detectors have addressed these challenges effectively in the hard X-ray regime, specifically with single photon counting pixel detectors extensively used in high-performance synchrotron applications, similar solutions are desired for energies below 2 keV. In this work, we introduce the first single-photon-counting hybrid pixel detector capable of detecting X-ray energies as low as 550 eV, utilizing the internal amplification of Low-Gain Avalanche Diode (LGAD) sensors. This detector is thoroughly characterized in terms of Signal-to-Noise Ratio and Detective Quantum Efficiency. We demonstrate its capabilities through ptychographic imaging at MAX IV 4th generation synchrotron light source at the Fe L-edge (707 eV), showcasing the enhanced detection performance of the system. This development sets a new benchmark for soft X-ray applications at synchrotrons, paving the way for significant advancements in imaging and analysis at lower photon energies.
Keywords
Cite
@article{arxiv.2503.04437,
title = {Single-photon counting pixel detector for soft X-rays},
author = {Filippo Baruffaldi and Anna Bergamaschi and Maurizio Boscardin and Martin Brueckner and Tim A. Butcher and Maria Carulla and Matteo Centis Vignali and Roberto Dinapoli and Simone Finizio and Erik Froejdh and Dominic Greiffenberg and Aldo Mozzanica and Giovanni Paternoster and Nicholas W. Phillips and Jörg Raabe and Bernd Schmitt and Jiaguo Zhang},
journal= {arXiv preprint arXiv:2503.04437},
year = {2025}
}