We present a novel single-photon detector based on a vacuum tube incorporating a photocathode, a microchannel plate (MCP), and a Timepix4 CMOS ASIC functioning as a pixelated anode. Designed to handle photon rates up to 1 billion per second across a 7 cm2 active area, the detector achieves outstanding spatial and temporal resolutions of 5-10 μm and below 50 ps r.m.s., respectively. The Timepix4 ASIC comprises approximately 230,000 pixels, each integrating analog and digital front-end electronics. This enables data-driven acquisition and supports data transmission rates up to 160 Gb/s. External FPGA-based electronics manage both configuration and readout. In order to test the timing performance of the Timepix4 ASIC we performed preliminary characterization of an assembly bonded to a 100 μm thick n-on-p silicon sensor using a pulsed infrared laser, which demonstrated a per-pixel timing resolution of 110 ps, with cluster-based averaging methods improving to below 50 ps. Six prototype detectors incorporating different MCP stack configurations and end-spoiling depths were produced by Hamamatsu Photonics. We report on their characterization, including dark count rates, gain, and spatial and timing resolutions, assessed both in laboratory conditions and during a test-beam campaign at CERN's SPS facility.
@article{arxiv.2602.01886,
title = {Development and characterization of hybrid MCP-PMT with embedded Timepix4 ASIC used as pixelated anode},
author = {Riccardo Bolzonella and Jerome Alozy and Rafael Ballabriga and Nicolò Vladi Biesuz and Michael Campbell and Viola Cavallini and Angelo Cotta Ramusino and Massimiliano Fiorini and Edoardo Franzoso and Marco Guarise and Xavi Llopart Cudie and Gabriele Romolini and Alessandro Saputi},
journal= {arXiv preprint arXiv:2602.01886},
year = {2026}
}