Radiation Effects in Silicon Photonics Micro-Ring Modulators and Waveguides for High-Energy Physics

by Daniele Alfiero (CERN/University of Birmingham)

Thursday 28 May 2026, 13:30 → 14:30 Europe/London

Small Lecture Theatre (Poynting)

Silicon photonics technologies have found major applications in optical transceivers for big data centres. For future high-energy physics experiments, silicon photonics-based transceivers are being investigated at CERN within the EP R&D programs. Recently, this technology has demonstrated promising radiation tolerance, making it increasingly suitable for such applications. This seminar will introduce the basic functionality of a silicon photonics transceiver, followed by a discussion of ionizing radiation effects on two key components: micro-ring modulators (MRMs) and photonic waveguides. The dynamic electro-optic response of the modulators is first characterized up to a TID of 12.3 MGy, including temperature effects and annealing studies that show an almost complete recovery of performance. Silicon photonics waveguides have been characterized through neutron test, showing a moderate increase in radiation-induced attenuation, and they have been investigated under heavy-ion irradiation for the first time, revealing a strong tolerance to optical single-event transients (OSETs). Preliminary TCAD simulation results are also presented, finding a good agreement with both the literature and the experimental heavy-ion measurements.