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Work Ultra-low-loss broadband multiport optical splitters on multiport optical couplers has been published in Optics Express and highlighted as Editor’s Pick. The research addresses the problem of efficient light splitting and routing in computing and communications. Imagine that several people now read this page as you do. Most of you want to look at the picture shown here and understand its details. To get this information efficiently to you all, the picture data are transferred from the Vinča Institute server by an optical cable and then split towards your respective network nodes. If one gets the incomplete data, e.g., with some parts cut out by the system limited bandwidth or loss, the figure would not look as pretty as it is. Thus, it is important to have devices that can split the signal into a number of equal signals that carry sufficient power and maintain the bandwidth of the original signal. These devices are multiport splitters. Conventional designs of multiport splitters rely on concatenation of curved directional couplers or conversion between single and multimode modes, both of which cause losses and need additional complicated structures to increase the bandwidth. Recent inversely designed nanostructured semiconductor splitters offer broad bandwidth operation, however, at high fabrication and design costs. In the published article, we present time and cost efficient inverse design and experimental realization of multiport splitters with near-zero insertion loss, broad bandwidth and small footprint. The new design is based on our previous work on single-mode linearly coupled waveguide arrays that support periodic light propagation. It allows for realisation of arbitrary splitting ratios by simple adjustment of separations of waveguides in the array. To demonstrate the technique, our partners Ms. Paloma Vildoso and Prof. Rodrigo Vicencio from the University of Chile have fabricated equal 1×N power splitters in a borosilicate wafer by femtosecond laser writing method. The splitters show zero insertion loss within the experimental error, bandwidth of 20−60 nm and low imbalance < 0.5 dB. Their footprint scales exponentially with the waveguide separation, which can be reduced to the limit of tight mode confinement. Remarkably, the splitting ratio can be adjusted by tuning the wavelength or the array length. The proposed splitters offer new possibilities for path-entanglement generation, multipath interferometery on chip and spatial mode multiplexing. For more information, see Optics Express 31, 12703 (2023) or e-mail jovanap@vin.ac.bg.rs.

Dr. Marko Spasenović from Institute of Chemestry, Technology and Metallurgy, University of Belgrade, will give a seminar: Detection of gases and physiological parameters with graphene sensors, 07/03/2023 at 10 am.

Prof. Manuel Algarra from Universidad Publica de Navarra, will give a seminar: Multifaceted Applications of Easiest Obtained Carbon Nanoparticles, 17/01/2023 at 12.

Prof. Janos K. Asboth from Budapest University of Technology and Economics, will give a seminar: Majorana Zero Modes in the Kitaev Wire: What, How, Why, 13/12/2022 at 13:30 via Zoom platform.

Prof. Marija Vucelja from the University of Virginia (USA), will give a seminar: Anomalous thermal relaxations in over-damped Langevin dynamics, antiferromagnets, and Random Energy Models, 25/10/2022 at 13:30 via Zoom platform.

Dr. Milica Matijević was awarded with the DAAD Research Stays for University Academics and Scientists for 2022. She will spend three months at the Institute of Medical Physics and Biophysics, Faculty of Medicine, University of Leipzig, where she will conduct the research work within the scope of the project „Cellular effects of the nanoplastics' encapsulated TiO2 fabricated by laser ablation”, Acronym: CONTRAST. Experiments will be performed under the supervision of Dr Irina Estrela Lopis.

Prof. Magnus Johansson from the Department of Physics, Chemistry and Biology (IFM) at Linkoeping University in Sweden, will give a seminar: Stability of breathers in nonlinear Schrödinger-type models, 24/05/2022 at 8 pm via Zoom platform.

Dr. Vladislav Jovanov from Institute of Chemestry, Technology and Metallurgy, University of Belgrade, will give a seminar: Thin layer solar cell and photodetectors, 11/05/2022 at 10 am.

Dr. Nikolay Afimov from Joint Institute for Nuclear Research Dubna will give a seminar: Neutrino physics at JINR, 26/04/2022 at 12 via Zoom platform.

The project in the field of technical and technological sciences: Multi-sensor system and artificial intelligence in service of heart failure diagnosis by our collegues Dr. Marija Ivanovic, Dr. Jovana Petrovic and Dr. Ljupco Hadzievski, has been selected for funding within the call Program IDEAS orginized by Science Fund of the Republic of Serbia.

Dr. Freek Ariese Principal Investigator from the LaserLaB Amsterdam (LLAMS), will give a seminar: Faster, stronger, deeper, etc: developments in Raman spectroscopy and imaging, 09/11/2021 at 12:30 via Zoom platform.

Prof. Rodrigo Vicencio from Chile University will give a seminar: Observation of inter-orbital coupling, 07/10/2021 at 13:30 via Zoom platform.

Paper Topological Charge Switch in Active Multi-Core Fibers is on the cover page of September issue of Annalen der Physik.

Member of the Center Dr. Ljupco Hadzievski (Scientific Adviser at the Institute of Nuclear Sciences Vinca - Coordinator for Cooperation of the Joint Coordination Committee of the Ministry of Education, Science and Technological Development and the Institute for Nuclear Research (OINI) in Dubna) has meeting on new opportunities and projects aimed at expanding scientific cooperation with Prof. Dr. Dmitry Kamanin, the Director of the Department for International Cooperation of the Joint Institute for Nuclear Research in Dubna.

Dr. Sinan Gundogdu from Humboldt University in Berlin will give a seminar: Direct laser writing waveguides in CR-39 polymer, 24/08/2021 at 11 am.

Prof. Nadezhda Bulgakova from Institute of Physics of the Czech Academy of Sciences in Pragu will give a seminar: HiLASE Centre - Scientific Laser Applications, 24/08/2021 at 11 am.

Morteza Kamalian Kopae from Aston University (UK) will give a seminar: Nonlinear Fourier analysis of a mode-locked laser, 07/08/2017 at 11 am.

Dr. Adenowo Gbadebo from Aston University (UK) will give a seminar: Advanced method of fabricating Fibre Bragg Gratings, 25/05/2017 at 11 am.

Dr. Nikita Tarasov from Aston University (UK) will give a seminar: Pattern recognition and classification of atrial activitie, 25/05/2017 at 10 am.

Prof. Boris Malomed from Tel Aviv University (Israel) will give a seminar: Old results and new perspectives in studies of multidimensional solitons, 24/06/2016 at 10 am.

P* sensor team on SNTV(2016).

Dr. Aleksandra Maluckov and Dr. Ljupčo Hadžievski won Award of the City of Belgrade (2015) for their work Stable optical vortices in nonlinear multicore fibres.

Dr. Nevena Ilić Raičević won the Best Poster Award at the Light Nanoscience and Nanotechnology Conference 2015 in Hissar, Bulgaria, with the poster Mach-Zehnder Interferometer with a Porous-Film Waveguide, N. Raicevic, A. Maluckov, J. Petrovic

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Prof. Francesco Cataliotti and prof. Augusto Smerzi from LENS, in visit, in July 2014.