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Researchers Aljaž Kavčič, dr. Maja Garvas, Matevž Marinčič and doc. dr. Matjaž Humar from the F5 department and dr. Boris Majaron from the F7 department of the Jožef Stefan Institute have, in collaboration with researchers from Graz University, published a paper in Nature Communications entitled Deep tissue localization and sensing using optical microcavity probes. In the paper they presented a new method for imaging through scattering tissues, based on localization of whispering gallery mode microresonators with spectrally narrow emission that enables a decomposition of diffuse signal into contributions from individual microresonators. The developed method combines the ability of precise localization on cellular level with possibility of sensing various parameters such as temperature, pH and refractive index, which makes it a versatile and promising tool in the field of deep-tissue imaging. First author of the paper Aljaž Kavčič presented the results of this work in his master’s thesis, for which he was awarded »Prešernova nagrada« of University of Ljubljana.

Associates of the Department of Condensed Matter Physics Tina Arh, Matej Pregelj, pHD, and prof. Andrej Zorko pHD, discovered the first realization of a quantum spin liquid on a Ising triangular-lattice antiferromagnet. They performed a large scale experimental study in collaboration with the researchers from the Slovenian Institute of Mathematics, Physics and Mechanics as well as researchers from India, Great Britain, France and the USA. The results were published in Nature Materials in the article The Ising triangular-lattice antiferromagnet neodymium heptatantalate as a quantum spin liquid candidate. In addition to being a significant scientific discovery, this discovery also has an important potential for the latest quantum technologies, as spin liquids are seen as one of the most perspective platforms in quantum computing.

Dr Luka Drinovec and Prof Griša Močnik, PhD: The Puh Award for outstanding achievements in the development of methods for measuring aerosol absorption, Ljubljana, The Government of the Republic of Slovenia

Asst. Prof. Anton Gradišek: Award for the best oral presentation at Ecobalt 2021 with the title “Particle Removal Efficiency of Face Masks During the Covid-19 Pandemic”, Riga, Latvia (virtual)

Asst. Prof. Anton Gradišek: Team JSI vs COVID won 2nd place at XPRIZE Pandemic Response Challenge for finding best strategies against covid, Culver City, California, USA, XPRIZE Foundation (virtual)

Prof Miha Ravnik, PhD: The Blinc Award for physicists at the beginning of their career, Ljubljana, Faculty of Mathematics and Physics and Jožef Stefan Institute

Aljaž Kavčič, MSc. Phys.: The Prešeren Award for his master‘s thesis “Microscopy and sensing through scattering tissues using optical microresonators” (mentor Asst. Prof. Matjaž Humar), Ljubljana, University of Ljubljana

Prof Samo Kralj, PhD: Award for outstanding achievements in higher education, Ljubljana, The Council for Higher Education of the Republic of Slovenia

Asst. Prof. Uroš Tkalec: The Blinc Award for extraordinary one-time achievement in physics for a research in the field of imbalanced complex fluids that was published in Nature Communications, Ljubljana, Faculty of mathematics and physics and Jožef Stefan Institute

Doc. dr. Matjaž Humar from the Department of Condensed Matter Physics at Jožef Stefan Institute, and researchers from UK, USA and Japan have published an article titled Whispering-gallery-mode sensors for biological and physical sensing in Nature Reviews Methods Primers. In the paper the authors introduce whispering-gallery-mode microcavities in different geometries, such as microspheres, microtoroids, microcapillaries and microrings. Whispering-gallery-mode microcavities are miniature micro-interferometers that use the multiple-cavity passes of light for very sensitive measurements at the microscale and nanoscale, including single-molecule and ion measurements. The authors describe sensing mechanisms, including mode splitting and resonance shift, and optomechanical and optoplasmonic signal transductions. Applications and experimental results cover in-vivo and single-molecule sensing, gyroscopes and microcavity quantum electrodynamics.

In an extensive study, Jeffrey C. Everts and Miha Ravnik from the Faculty of Mathematics and Physics at University of Ljubljana and the Department F5 of Jožef Stefan Institute examined the details of the coupling of ions and singular topological defects in complex nematic fluids (Phys. Rev. X 2021). The authors showed that topological defects in nematic electrolytes could perform as areas for local separation of electric charge, forming electrically charged cores of defect and in selected geometries also electrical multi-layers. These charge distribution are generalizations of electrical double layers known in isotropic electrolytes. In particular, they show that ions couple very efficiently with the defect cores through the mechanism of ionic solubility, and with the surrounding orientation field deformations through the mechanism of flexoelectricity. The work is a significant contribution towards understanding the electrostatic mechanisms in complex soft matter.