Guest Editors
Francesco Villasmunta
Technical University of Applied Sciences Wildau
Francesco Villasmunta was born in Bari, Italy. He earned his BSc in Physics from the University of Bari Aldo Moro in 2015, his MSc in Materials Science and Technology from the University of Rome Tor Vergata in 2018, and his M.Eng. in Photonics from the Technical University of Applied Sciences Wildau (TH-Wildau), Germany, also in 2018. Currently, he is pursuing a PhD at Brandenburg University of Technology Cottbus-Senftenberg (BTU) in collaboration with TH-Wildau, Germany. Since 2018, he has worked as a scientific researcher at TH-Wildau and held a guest scientist position at IHP: Leibniz Institute for High-Performance Microelectronics. His research focuses on silicon photonic interconnections, with expertise in deep reactive ion etching (DRIE), including both Bosch and cryogenic ICP-RIE techniques, as well as optical simulations and metrology. Francesco has authored several publications and filed a patent application for integrated optical waveguides. He was also awarded the TH-Wildau Research Prize for 2025.
Patrick Heise
Technical University of Applied Sciences Mittelhessen
Dr. Patrick Heise (formerly Patrick Steglich, Senior Member, IEEE) earned his MSc in Photonics from the Technical University of Applied Sciences Wildau, Germany, in 2013, and his PhD from the University of Rome "Tor Vergata," Italy, in 2017. From 2018 to 2023, he worked as a senior researcher at IHP: Leibniz Institute for Innovative Microelectronics in Germany, and he has been affiliated with the institute as a guest scientist since 2023. He completed his habilitation in experimental physics at Brandenburg University of Technology Cottbus-Senftenberg in 2023. Dr. Heise's research interests include silicon photonics, microelectronics, and biomedical sensors. As a co-founder of HyPhoX, he received several accolades, including the Leibniz Founding Award in 2021, the Berlin-Brandenburg Innovation Award in 2023, and the Digital Innovation Award from the German Federal Ministry for Economic Affairs and Climate Action in 2024. Since 2025, he has held the position of full professor of biomedical electronics at the Technical University of Applied Sciences Mittelhessen, Germany.
Collection Overview
Photonic integrated circuits (PICs) revolutionize sensing and communication technologies by enabling compact, scalable, and highly sensitive devices. As PIC-based sensors find increasing application in fields such as biomedical diagnostics, environmental monitoring, quantum technologies, and next-generation data communications, robust and standardized characterization methods are becoming essential.
Modern PICs span a variety of material platforms, including silicon, silicon nitride, indium phosphide, lithium niobate, and emerging polymers, each tailored for specific spectral ranges, integration levels, or electro-optic functionalities. Alongside these materials, electromagnetic simulations, numerical modeling, and inverse photonics design enable highly efficient, compact, and application-specific components such as grating couplers, multimode interferometers, and mode-division multiplexers. These advanced design techniques, however, often demand more refined and specialized characterization procedures.
This Methods Collection aims to provide the research community with a comprehensive set of experimental protocols for the optical, electrical, and thermal characterization of sensors and devices based on photonic integrated circuits. By offering visual demonstrations of coupling strategies, loss measurements, spectral response testing, and mode profiling, this collection will support new and experienced researchers in achieving consistent and accurate results. It will address practical techniques across diverse platforms and device architectures, including those designed using inverse methods that push the limits of conventional testing approaches.
The goal is to build a foundational resource that enhances reproducibility and accelerates innovation in photonic sensor development. By standardizing key procedures and making them visually accessible, this Methods Collection will lower entry barriers for new labs, streamline training, and foster cross-disciplinary applications of integrated photonic technologies.
Abstracts
Top-Down Testing of Integrated Photonic Devices
Mark Harrison*1
1Chapman University