Hybrid Event

Event program

Tuesday, 5/26/2026 3:00 PM - 7:00 PM, Nava 1, Hotel Admiral, Opatija 15:00 - 17:00      Invited Lectures  15:00 - 15:40 David Vitali (University of Camerino, Italy) Quantum Sensing and Quantum Transduction with Optomechanical Devices  15:40 - 16:20 Eric Langman (Qfactory ApS, Copenhagen, Denmark) Phononic Crystal Electromechanics for Commercial and Not-So-Commercial Applications  16:20 - 17:00 Massimiliano Rossi (DelD University of Technology, Netherlands) Towards Large Delocalisation of Levitated Nanoparticles  17:00 - 17:20     Break  17:20 - 17:45      Presentation  P. Andrekson (Chalmers University, Gothenburg, Sweden) Optical Phase-sensitive Parametric Amplifiers for Optical Communication in Space  Optical parametric amplifiers (OPAs) have several features that fundamentally differ from other optical amplifiers. This includes the possibility to amplify light waves without adding excess noise (which is the case for amplifiers relying on stimulated emission) when implemented in the phase-sensitive mode. I will review our experimental results on OPAs demonstrating ultrabroadband operation using in-house fabricated nonlinear silicon-nitride waveguides as the nonlinear medium and, in particular, the use of ultralow noise OPAs as preamplifiers for very sensitive optical receivers. These OPA currently rely on nonlinear optical fibers, and we demonstrated a sensitivity as low as 1 photon per information bit at a rate of 10 Gb/s. We also compare this to fundamental limitations, and to other sensitive approaches, all of which show promise for deep space communication links using light as a carrier of data rather than microwaves as today. 17:45 - 19:00      Papers  1. M. Jagnjić, J. Vuković, J. Lončar (University of Zagreb, Faculty of Electrical Engineering and Computing, Department of Communication a, Zagreb, Croatia), M. Lončarić (Ruđer Bošković Institute, Division of experimental physics, Laboratory for photonics and quantum opt, Zagreb, Croatia), D. Babić, D. Bojanjac (University of Zagreb, Faculty of Electrical Engineering and Computing, Department of Communication a, Zagreb, Croatia) An Update on the Optical Ground Station Design for Croatian Quantum Communication Infrastructure  The European efforts to establish a quantum-safe communication infrastructure have motivated the development of advanced optical ground stations (OGS) capable of supporting satellite quantum key distribution (QKD). Building on the previously proposed concept of the first Croatian optical ground station for quantum communications in Zagreb (OGSZG), this work presents an updated system design. The OGSZG comprises a Ritchey–Chrétien telescope with a Coudé path optimized for C-band operation, a motorized dome and telescope mount designed to track low-Earth-orbit satellites, and a dedicated Coudé laboratory with a QKD node. The station integrates wide and narrow field-of-view cameras as part of the pointing, acquisition, and tracking (PAT) system, together with a tip-tilt compensation unit to correct beam wander induced by atmospheric turbulence and pointing jitter. The design has been developed with future upgrades in mind, including adaptive optics, a classical laser communication terminal, and the Eagle-1-compatible quantum receiver required for a fully functional quantum communication ground segment. 2. V. Puligandla, N. Popov, T. Knezevic (Ruder Boskovic Institute, Zagreb, Croatia) Study Of Photochromic Material-based Weighting For Optical Neural Networks  Despite the promise of high-bandwidth and computation at the speed of light, conventional optical neural networks (ONN) realized in photonic integrated circuits (PIC) suffer from the predominant use of electric heaters for weight multiplication which imposes a high energy cost. These thermal-optic phase shifters suffer from high energy consumption to maintain the weights and are susceptible to noise due to heat dissipation. Recent studies focused on organic photochromic materials demonstrate a promising alternative for ONN weighting in a non-volatile and reversible manner with low loss when operated in the low photon regime. In this work, we study the photochromic properties of diarylethene derivatives embedded in polymer films to implement ONN weights. We used experimental data to determine the optimal wavelengths for efficiently driving the forward (ring-opening) and reverse (ring-closing) isomerizations that modulate optical transmission. Optical neural network simulations are used to study the principles of photochromic weighting in neural network architectures. The performance of the selected neural network architectures is studied under variations in the fabrication of thin films of the photochromic material. The effects of potential weight-encoding errors from photochromic weighting are analyzed in detail. 3. K. Vörös (John von Neumann Faculty of Informatics, Obuda University, Budapest, Hungary), M. Kozlovszky (BioTech Research Center, Obuda University, Budapest, Hungary) Quantum Communication and Game Theory with Nonclassical Correlations  Classical game theory is constrained by the limits of local realism. This paper presents simple problems from game theory, where pre-shared entangled states and nonclassical correlations (specifically Popescu-Rohrlich boxes) allow players to exceed classical winning probabilities. We provide a rigorous mathematical foundation for bipartite and multipartite quantum systems, analyzing the spectral decomposition of operators and tensor product eigenproblems. Four specific games are analyzed: the CHSH game, Strong/Weak Coin Flipping, the Casino Game, and Magic Squares. We demonstrate that for the Magic Square game, quantum resources transition the optimal winning probability from 8/9 to certainty of probability 1. Finally, we reference to a Python-based desktop application of our previous work, that emulates non-local correlations using a hardware-assisted quantum API. Wednesday, 5/27/2026 3:00 PM - 7:00 PM, Nava 1, Hotel Admiral, Opatija 15:00 - 17:00      Invited Lectures  15:00 - 15:40 Regina Gumenyuk (Laboratory of Photonics, Tampere University, Finland) Pushing the Limits of Picosecond Fiber Lasers with Active Tapered Fiber Amplifiers  15:40 - 16:20 Andrej Lavrič, Boštjan Batagelj (Faculty of Electrical Engineering, University of Ljubljana, Slovenia) Fiber-Optic Delay-Line for Phase Noise Measurement of Microwave Sources  16:20 - 17:00 Arnaud Mussot (Faculty of Science and Technologies, University of Lille, Villeneuve-d'Ascq, France) Multiple Frequency Combs in Multicore High Quality Factor Fiber Fabry-Perot Resonators  17:00 - 17:20      Break  17:20 - 17:45      Presentation  B. Resan, M. Zeyen (University of Applied Sciences and Arts Northwestern Switzerland, Windisch, Switzerland) Ultra-high Resolution Optics Coherence Tomography Imaging with Low Cost Blue Diode Pumped Ti:Sapphire Laser and Axicon Lens  We will present our recent results in Optical Coherence Tomography 3D imaging of challenging biomedical tissues reaching 2-3 microns axial and lateral resolutions. This ultra-high resolution is enabled by use of the novel blue laser diode pumped Ti:Sapphire laser providing broad band-width and high power to overcome the losses of axicon lens. We will present imaging of transpar-ent gel and opaque bone marrow tissues. 17:45 - 19:00      Papers  1. K. Stojšić, V. Vujnović, S. Jurković (Medical Physics and Radiation Protection Department, University Hospital Rijeka, Rijeka, Croatia) Fiber-Optic Thermometry for Fetal-Like MRI Phantoms: Design Considerations for PRFS Validation  Accurate temperature ground truth is essential for validating magnetic resonance (MR) thermometry in fetal imaging, where proton resonance frequency shift-based (PRFS) temperature maps are degraded by maternal/fetal motion, susceptibility changes at fluid–tissue interfaces, and scanner B0 drift. We present a biophotonic instrumentation proposal that defines a future workflow coupling a fetal-like, multi-compartment MR phantom with fiber-optic thermometry. We propose a 3D design of a fetal MR phantom with interchangeable compartments and embedded channels for sensor placement and routing. We then specify an MR-compatible optical temperature measurement concept using discrete fluoroptic probes and/or multiplexed Fiber Bragg Grating arrays, including source and interrogator options, wavelength-division multiplexing, sampling-rate requirements, and synchronization with MR acquisitions. Optical-physics-driven design improvements are proposed to reduce systematic error: low-susceptibility, low-conductivity sensor packaging, grating-length selection to mitigate strain–temperature cross-sensitivity and spatial averaging in thermal gradients. 2. N. Malivuk, I. Putnik, B. Kuzmanović, J. Bajić, F. Mrkić, S. Cvetićanin, S. Kojić (Faculty of Technical Sciences, University of , Novi Sad, Serbia) Mechanical and Optical Characterization of SLA-Printed Photopolymers for Microfluidic Applications  Microfluidic Lab-on-Chip (LOC) systems require structurally stable and optically compatible materials to ensure reliable fluid manipulation and accurate optical detection. Although polydimethylsiloxane (PDMS) remains widely used, its mechanical limitations and limited scalability have encouraged the adoption of stereolithography (SLA)-based photopolymers. However, systematic mechanical and optical characterization data relevant to microfluidic design remain insufficient. This study presents a comprehensive evaluation of six commercially available SLA photopolymers, including rigid, engineering, and transparent dental-grade formulations. Specimens were fabricated via vat photopolymerization under controlled printing parameters and subjected to post-curing. Mechanical characterization was performed according to ISO 527-2 using uniaxial tensile testing to determine ultimate tensile strength and elongation at break. Optical characterization was conducted using a compact spectrometer in the 200–1000 nm spectral range to quantify wavelength-dependent transmission behavior. The influence of autoclave sterilization (121 °C, 15 min) on material performance was additionally investigated. The experimentally obtained parameters provide quantitative insight into load-bearing capacity, deformation limits, and spectral compatibility with optical sensing techniques. The results establish a practical framework for evidence-based material selection, predictive modeling, and optimized structural design of SLA-fabricated microfluidic and LOC platforms intended for biomedical and bioengineering applications. 3. A. Benna Unni, P. Velayudhan (August Chełkowski Institute of Physics, University of Silesia in Katowice, Katowice, Poland), Y. Fondjo Latta Eugène (University of Le Mans. Faculty of Science and Technology, Le Mans, France), R. Mehyaoui (Materials Science and Applications Laboratory (LSMA), Faculty of Sciences and Technology, Ain-Temouchent, Algeria), K. Adrjanowicz (August Chełkowski Institute of Physics, University of Silesia in Katowice, Katowice, Poland) Substrate-Induced Modulation of Dynamics in Vapor-Deposited Glasses  The long-term operational stability of organic optoelectronic devices, such as Organic LightEmitting Diodes (OLEDs), is governed by the kinetic stability and relaxation dynamics of amorphous molecular thin films. In this work, we investigate the glass dynamics of Celecoxib (CXB), employed as a model system for organic semiconductors, across a range of nanometric thicknesses (30–100 nm). Using physical vapor deposition (PVD), we compare the behavior of standard vapordeposited glasses with ultra-stable glasses (USGs) prepared at optimized substrate temperatures. Our study systematically explores the influence of diverse substrates—specifically Chromium (Cr), Gallium Arsenide (GaAs), and Silicon (Si) wafers—on the molecular mobility of these films. We correlate these dynamical observations with the thermodynamic work of adhesion determined through contact angle goniometry. We observe strong substrate-dependent dynamics in conventional glasses that disappear beyond a critical thickness, while USGs exhibit decoupling from substrate effects even in confined films. These results provide practical guidelines for designing more stable and reliable organic optoelectronic devices.

Basic information:

Nenad Kralj (Croatia), Darko Zibar (Denmark), Marija Furdek Prekratić (Sweden)

Toni Aaltonen (Finland), Ticijana Ban (Croatia), Borko Baraban (Croatia), Bruno Blašković (Croatia), Hrvoje Buljan (Croatia), Domenico Caputo (Italy), Vedran Dakić (Croatia), Michele de Santis (Italy), Pedro Faria (Portugal), Jonas Junker (Denmark), Tihomir Knežević (Croatia), Petar Kolar (Croatia), Branimir Kolarek (Croatia), Robert Kudelić (Croatia), Ivica Lukić (Croatia), Danilo Marić (Italy), Tomislav Matić (Croatia), Lucia Načinović Prskalo (Croatia), Norman Nelufule (South Africa), Kerim Obarčanin (Sweden), Ana Oprescu (Netherlands), Tomasz Pełech-Pilichowski (Poland), Justin M. Pelletier (United States), Ayodele Periola (South Africa), Ioan Ștefan Sacală (Romania), Karolj Skala (Croatia), Zvonimir Šipuš (Croatia), António Teixeira (Portugal), Benny Thörnberg (Sweden)
 

Registration / Fees:

The student discount doesn't apply to PhD students.

NOTE FOR AUTHORS: In order to have your paper published, it is required that you pay at least one registration fee for each paper. Authors of 2 or more papers are entitled to a 10% discount.

Nenad Kralj
University of Rijeka
Faculty of Physics
Radmile Matejčić 2
HR-51000 Rijeka, Croatia
e-mail: nenad.kralj@phy.uniri.hr 

Darko Zibar
Technical University of Denmark
Department of Electrical and Photonics Engineering
Orsteds Plads, Building 343, Room 124
2800 Kgs. Lyngby, Denmark
e-mail: dazi@dtu.dk 

Marija Furdek Prekratić
Chalmers University of Technology
Department of Electrical Engineering
Horsalsvagen 11
412 96 Gothenburg, Sweden
e-mail: furdek@chalmers.se
 

The best papers will get a special award.
Accepted papers will be published in the ISSN registered conference proceedings. Papers in English presented at the conference will be submitted for inclusion in the IEEE Xplore Digital Library. 

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