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The paper entitled Network traffic modeling for load prediction: a user-centric approach published in IEEE Network, authored by two researchers from the Department of communications systems prof. dr. Aleš Švigelj and dr. Kemal Alič and dr. Radovan Sernec from Telekoma Slovenije, was selected for the Best Paper Award of the IEEE ComSoc Technical Committee on Communications Systems Integration and Modeling. The award will be presented during the prestigious IEEE Globecom 2016 conference held in December in Washington D.C., USA. The paper addresses an innovative user-centric approach to network traffic modelling that was validated and used in the process of introducing, optimizing, and planning of new services at the Slovenian national telecom operator and service provider.


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Matjaž Humar from Condensed Matter Physics department at Jožef Stefan Institute won 1st Place Poster Prize at prestigious Nobel Laureate Meeting 2016. The meeting has taken place in Lindau, Germany from 26. June to 1. July. There were 400 invited young scientists from 80 countries and 29 Nobel laureates attending the 66. Lindau Nobel Laureate Meeting. The attendees of the meeting are carefully selected by a committee giving priority to young scientists who are strongly committed to science and research. This year meeting was focused on physics. Matjaž presented a poster about lasers embedded into single live cells. His poster got the most votes given by the young scientists and Nobel laureates.


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Researchers from the Department of Automation, Biocybernetics and Robotics at Jožef Stefan Institute in collaboration with the colleagues from Technical University Darmstadt in Germany have revealed mechanisms of how human central nervous system controls the motion of our body during physical interaction with the environment. They examined adaptation to systematic postural perturbations while the human subjects had to perform a series of goal oriented movements. By employing a novel probabilistic modeling approach, the researchers established a computational model that explained how our brain arbitrates between goal oriented movements and maintaining postural balance. The findings of the study were published by Nature Scientific reports.


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On May 23 and 24, 2016 Prof. Kiyoshi Tanaka, a Vice-President of Shinshu University, Nagano, Japan, and Hernán Aguirre, an Associated Professor at Shinshu University, were visiting the Jožef Stefan Institute. The purpose of the visit was to start a scientific cooperation between the two institutions supported by the Slovenian Research Agency and Japan Society for the Promotion of Science. To this end, the two sides agreed on a memorandum that was signed by the Director of JSI Prof. Jadran Lenarčič on May 24. The joint research focuses on multi-criteria optimization for space exploration and infrastructure networks. At JSI it is conducted by the Computational Intelligence Group of the Department of Intelligent Systems led by Prof. Bogdan Filipič.


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The journal Scientific Reports published on May 20, 2016 the article entitled "Points, skyrmions and torons in chiral nematic droplets", by Gregor Posnjak, Simon Čopar and Igor Muševič, members of the Solid State Department (F5) of JSI and Faculty of Mathematics and Physics, University of Ljubljana. They discovered a new method of reconstructing 3D orientational field of a liquid crystal, labelled with fluorescent molecules and imaged with a confocal optical microscope. Using this method they were able for the first time to determine unambigously the topological properties of a chiral liquid crystal, captured in a micro-droplet, as tiny as a hair. They could see singular point-like topological defects, separated by 3D topological objects, which are known in physics as skyrmions and torons.


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On Monday, 16 May 2016 the group led by Prof. Dr. Dragan Mihailović from department of Complex Matter, Jozef Stefan Institute published an article entitled Fast electronic resistance switching involving hidden charge density wave states in Nature Communications. The article describes the way for electrical control of a new type of memory element with a record speed. Nowadays the speed of memory is the main constraint slowing down supercomputers, which everybody of us is using while surfing Google, Amazon, eBay, etc. Experimental work, in which the main contributors are dr. Igor Vaskivskyi, Ian Mihailović and Damjan Svetin, describes a record fast electrically driven memory element, in which the writing process occurs in just 40 picoseconds. The previous world record was held by an American group. The group of Jozef Stefan Institute improved their record by about 10 times.


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Researchers from the Jožef Stefan Institute (Department for Materials Synthesis and Department for Complex Matter) and the University of Ljubljana, Darja Lisjak, Alenka Mertelj and Martin Čopič, in collaboration with researchers from the USA (University in Boulder, Lawrence Berkeley National Laboratory and Case Western Reserve University) have discovered that suspensions of magnetic nanoplatelets in butanol exhibit ferromagnetic ordering. Its zero-field magnetization produces distinctive magnetic self-interaction effects, including liquid-crystal textures of fluid block domains arranged in closed flux loops, and makes this phase highly sensitive, with it dramatically changing shape even in the Earth’s magnetic field. The discovery was published in Nature Communications.


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Matjaž Humar from Jožef Stefan Institute, Condensed Matter Physics, who is currently a Marie Curie fellow at Harvard Medical School, has published in collaboration with researchers from Massachusetts General Hospital an article Bioabsorbable polymer optical waveguides for deep-tissue photomedicine in Nature Communications. The authors made a new class of optical waveguides for deep-tissue photomedicine made out of biocompatible and biodegradable polymer materials, which can be implanted into the body and are naturally degraded over time. The waveguides enable the use of a number of medical laser treatments and diagnostics deep into the body, which were till now only limited to the surface of the body due to limited penetration of light into the tissues. As an example of a possible application, laser wound closure is demonstrated, leading to faster healing and less scarring.


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Julian Walker, Hana Uršič, Andreja Benčan, Barbara Malič and Tadej Rojac from the Electronic Ceramics Department (K-5), in collaboration with researchers from Denmark, Russia, Portugal and Australia, published their work ˝Dual strain mechanisms in a lead-free morphotropic phase boundary ferroelectric˝ in the January 2016 issue of Nature Scientific Reports (DOI: 10.1038/srep19630). The work focuses on (Bi,Sm)FeO3 compositions at the morphotropic phase boundary, where they identified a previously unreported electric-field-induced phase transition. The authors demonstrate the unique occurrence of dual strain mechanisms consisting of ferroelastic domain switching and a field-induced phase transition, which simultaneously contribute to the macroscopic strain behaviour of these lead-free ferroelectric materials.


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N. Kostevšek, S. Šturm and K. Žužek Rožman from the Jožef Stefan Institute, Department for Nanostructured Materials, in collaboration with partners from Bologna, Trieste and Torino, have published in Chemical Communications an article entitled The one-step synthesis and surface functionalization of dumbbell-like gold–iron oxide nanoparticles: a chitosan-based nano-theranostic system. It was shown that the hybrid Au-Fe oxide nanoparticles, equipped with a biocompatible chitosan coating, are introducing an effective system for biomedical diagnostics and therapy. As prepared, nanoparticles exhibit photo-acoustic effect, which presents a new and non-invasive way of imaging. Moreover, their photo-thermal response can be used for an efficient and selective treatment of the targeted tissues.


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Researchers from the Condensed Matter Physics and Complex Matter Physics departments of the Jožef Stefan Institute, in collaboration with partners from Belgium, France and Germany, have shown that the slow anion diffusion in anion-exchange reactions can be efficiently used to tune the disorder strength and the related electronic properties of nanoparticles. This was shown for the case of titanium oxy-nitride nanoribbons. By controlling the nitrogen content, which determines the chemical disorder through random O/N occupancy and ion vacancies, they effected the transition from “bad metal” to the superconducting state. This shows that with anion exchange, not only can the structural order be affected, but so can the physical and functional properties of these materials. The results were published in the journal ACS NANO.


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The magnetic response of magnetic insulators is determined by the coupling between the magnetic moments, which is usually temperature independent. A theoretical work dating from the 1980s showed that the eventual temperature dependence originates from the thermal expansion of the lattice, while the contribution of the lattice vibrations could be considered negligible. In contrast, Martin Klanjšek and Denis Arčon from the Condensed Matter Physics department at the Jožef Stefan Institute, together with German colleagues who synthesized the sample, showed that the magnetic coupling in caesium superoxide is strongly temperature dependent, precisely as a result of the librations of the magnetic superoxide molecules. This first confirmation of the dynamic modulation of the magnetic coupling, a prototypical phenomenon relevant for a range of other molecular magnets, is described in the recently published article in Physical Review Letters.


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Researchers at the Jožef Stefan Institute have succeeded in making a very important breakthrough - for the first time they were able to implant a laser into a single human cell. Furthermore, they have demonstrated that the fat cells in our body already contain lasers, which need only to be activated. In both cases the lasers are in the form of small solid spheres or lipid droplets. Deformation of the droplets enables accurate measurements of the forces inside the cells. The emission of each laser within a cell can also be used as a barcode with enough unique combinations to tag all the cells in the human body. This discovery was published in the Nature Photonics paper Intracellular microlasers. The authors are Dr Matjaž Humar from the Condensed Matter Physics department of the JSI, who is currently on a postdoc at Harvard Medical School, USA, and Seok-Hyun Yun - video.


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On 12 June 2015, the journal Nature Communications published an article entitled “Spin-stripe phase in a frustrated zigzag spin-1/2 chain”, by Matej Pregelj, Andrej Zorko and Denis Arčon from the Condensed Matter Physics (F5) department at the Jožef Stefan Institute, in collaboration with partners from Switzerland, France and Japan. The results unveil the beta-TeVO4 compound as a model system of a frustrated spin chain. The main result is the discovery of a magnetic stripe structure on the nanoscale, which appears at the transition between the spiral and collinear magnetic orders. In contrast to known modulated electron systems, in beta-TeVO4 the stripes are stabilized in the absence of long-range interactions. The presented system thus allows a better understanding of the origin of the intriguing nanometre-sized modulation in other systems, e.g., high-temperature superconductors.


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Researchers at the Jožef Stefan Institute have identified an unexpectedly general set of rules that determine which molecules can cause the immune system to become vulnerable to the autoimmune disorders lupus and psoriasis. Autoimmune diseases strike when the body attacks itself because it fails to distinguish between host tissue and disease-causing agents, or pathogens. When a healthy person is infected by a virus, viral DNA can activate the immune cells via a receptor called TLR9. The receptor triggers the cells to send signalling molecules called interferons to initiate a powerful defensive response. In people with lupus or psoriasis, these cells are activated by their own DNA, or self-DNA. A team of scientists has shown that the process of DNA-induced amplification of interferon production is more physical in nature than had been expected. An interplay of electrostatics and multivalent binding results in multivalent activation: only those complexes with a DNA interstrand spacing corresponding to the dimensions of the toll-like receptor binding sites trigger a strong immune response.


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With an important contribution from Denis Arčon, Peter Jeglič and Anton Potočnik from the Solid State Physics Department, a new type of metallic state of matter has been discovered by an international team of researchers studying a superconductor made from C60 molecules. The team found this new metallic state after changing the distance between neighbouring C60 molecules by doping the parent Cs3C60 material with rubidium. The study revealed that the material has a remarkably rich combination of insulating, magnetic, metallic and superconducting phases – including the hitherto unknown state, which the researchers have dubbed a "Jahn–Teller metal". The article was recently published in Science Advances, a new research journal of AAAS (Science), and has been picked up by several news sources, including physicsworld.com.


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On 15 May 2015, the Advanced Functional Materials journal published the article Controllable Broadband Absorption in the Mixed Phase of Metamagnets, written by Matej Pregelj, Andrej Zorko and Matjaž Gomilšek from the Condensed Matter Physics department at the Jožef Stafan Institute, in collaboration with partners from Switzerland, Germany and Moldova. The article reveals the ability of metamagnetic materials to absorb electromagnetic radiation across an extremely broad frequency range. The effect is controlled by an external magnetic field, which actuates a mixed ferro/antiferromagnetic phase, where the absorption in the Cu3Bi(SeO3)2O2Br system extends over at least nine orders of the frequency scale. Considering that artificial metamagnets (magnetic multilayers) allow for direct control over the required magnetic field, a novel way of tuning the material’s properties is imminent.


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On 15 May 2015, the Advanced Functional Materials journal published the article Controllable Broadband Absorption in the Mixed Phase of Metamagnets, written by Matej Pregelj, Andrej Zorko and Matjaž Gomilšek from the Condensed Matter Physics (F5) department at the Jožef Stafan Institute, in collaboration with partners from Switzerland, Germany and Moldova. The article reveals the ability of metamagnetic materials to absorb electromagnetic radiation across an extremely broad frequency range. The effect is controlled by an external magnetic field, which actuates a mixed ferro/antiferromagnetic phase, where the absorption in the Cu3Bi(SeO3)2O2Br system extends over at least nine orders of the frequency scale. Considering that artificial metamagnets (magnetic multilayers) allow for direct control over the required magnetic field, a novel way of tuning the material’s functional properties is imminent.


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Asst. Prof. Tadej Rojac, Dr Hana Uršič, Asst. Prof. Andreja Benčan and Prof. Barbara Malič from the Electronic Ceramics Department, Jožef Stefan Institute, in collaboration with Prof. Dragan Damjanović, from the Swiss Federal Institute of Technology, published their recent results on Mobile Domain Walls as a Bridge between Nanoscale Conductivity and Macroscopic Electromechanical Response in Advanced Functional Materials. They showed that in polycrystalline BiFeO3 the local domain-wall conductivity within the grains results in an unexpectedly large effect on the macroscopic piezoelectric response. Their results bridge the local conductivity and the macroscopic piezoelectricity via domain-wall dynamics, revealing that the domain-wall conductivity must be considered when interpreting and controlling the macroscopic electro-mechanical properties of piezoelectric ceramics.


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Caesium atoms have been trapped and cooled for the first time in the Laboratory for Cold Atoms at the Solid State Physics Department of the Jožef Stefan Institute in collaboration with the Theoretical Physics Department and Low and Medium Energy Physics Department. A view through the vacuum chamber viewport shows a fluorescing tiny pink cloud containing 50 million caesium atoms levitating at a few hundred microkelvin. In the next step, the atoms will be transferred to the dipole trap produced by high-power laser light and finally cooled down by evaporation to reach temperatures below 50 nanokelvin, where the Bose-Einstein condensation takes place. More information about the laser cooling and trapping methods is available at ultracool.ijs.si.


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In a recently published article in Nature Physics prof. J. Bonča from the Department of Theoretical Physics, together with his former PhD students, dr. L. Vidmar and dr. D. Golež, and an experimental group from Italy, addressed one of the pivotal questions in the physics of high-temperature superconductors concerning the question of whether the low-energy dynamics of the charge carriers is mediated by bosons with a characteristic timescale. The answer to this question has remained elusive as electronic correlations are expected to greatly accelerate the electron–boson scattering processes, confining them to the very femtosecond timescale. The experimentally observed timescale is in agreement with numerical calculations on a model in which the relaxation of the photo-excited charges is achieved via inelastic scattering with short-range antiferromagnetic excitations.


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Silver(II) compounds exhibit a broad range of peculiar physicochemical properties, which are described in the review "Chemistry of Silver(II): a Cornucopia of Peculiarities" written by Wojciech Grochala of the University of Warsaw and Zoran Mazej of the Jožef Stefan Institute. Their review paper has been published in the journal Philosophical Transactions A, published by the Royal Society (London). Phil. Trans. R. Soc. A is the oldest journal in the world that is dedicated only to science. The first issue appeared in March 1665, and so this year the journal is celebrating its 350th anniversary. Each issue is focused on a specific topic. The 13 March 2015 issue, in which the paper is published, has the title "The new chemistry of the elements" and is dedicated to the importance of the periodic table.


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The PNAS journal, which is celebrating its 100th anniversary in 2015, has recently published a paper entitled Knot theory realizations in nematic colloids, by Simon Čopar, Uroš Tkalec, Igor Muševič and Slobodan Žumer from the Faculty of Mathematics and Physics in Ljubljana, the Faculty of Natural Sciences and Mathematics in Maribor, and the Solid State Physics Department of the Jožef Stefan Institute.
The authors report diverse applications of knot theory in nematic liquid-crystal colloids with knotted defect loops. The results demonstrate how the construction of graphs, topological surfaces and knot polynomials is showcased directly on experimental micrographs, thereby identifying the entangled structures without the need for numerical simulations. The paper illustrates how abstract mathematical concepts manifest elegantly as observable features in soft-matter physics.


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Dr Marko Soderžnik, working on the FP7 project entitled “Replacement and Original Magnet Engineering Options (ROMEO)”, which is coordinated by prof. Spomenka Kobe, substantially contributed to the success of the JSI team. Fundamental research was the basis for a highly innovative technology, developed within the department. The technology is based on electrophoretic deposition and a sophisticated heat-treatment method for selective diffusion along the grain boundaries of the magnet. This technology has resulted in the project’s ambitious target magnetic properties being achieved. The process is now in the testing stage at Vacuumschmelze’s pilot line in Hanau, Germany. The final result will be high-energy magnets with the minimum content of valuable heavy rare earths. These magnets will be used in a prototype Siemens demonstrator motor for wind turbines as part of the ROMEO project.


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The Austrian institute Joanneum Research held its FORUM ROBOTICS on 21 January 2015 in Graz, Austria. The plenary lecture entitled "Robots can learn!" was presented by Prof. Jadran Lenarčič, Director of the Jožef Stefan Institute, in which he described the latest advances in the area of robotics as well as his vision of the future. Among the attendees were prof. Wolfgang Prybil, President of Joanneum Research, and Mr Christopher Drexler, a member of the Provincial Government of Styria.
The Jožef Stefan Institute and Joanneum Research have been actively collaborating across a variety of fields since 2005, when the original collaboration agreement was signed. Joanneum Research has recently opened a new robotics division in Klagenfurt, Austria, which will create excellent opportunities for joint research and technology development projects.


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On 22 December 2014 the journal Nature Physics published an article entitled Light-controlled topological charge and a Nematic Liquid Crystal , written by Maryam Nikkhou, Miha Škarabot, Simon Čopar, Miha Ravnik, Slobodan Žumer and Igor Muševič, from the Department for Solid-State Physics (F5) of the Jožef Stefan Institute and the Faculty of Mathematics and Physics, University of Ljubljana. Their paper describes experiments in which a strong laser light is used to create and stabilize a pair of topological defects in liquid crystals formed by a defect and an anti-defect or a "particle" and an "antiparticle". The picture shows the liquid crystal, as seen under a microscope, only a few milliseconds after the laser pulse. This pulse leads to the formation of a dense network of topological defects, from which eventually pairs of topological defects are formed. This is reminiscent of the Kibble-Zurek mechanism for the production of monopoles in cosmology. This means that by using the theory of the dynamics of the provisions for annihilation and basic topological rules we can observe the mechanisms for the production topological charge.


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Members of the Jožef Stan Institute’s Department of Theoretical Physics (F1), Luca Tubiana and Rudolf Podgornik, as well as a former members Anze Losdorfer Bozic and Christian Micheletti of La Scuola Internazionale Superiore di Studi Avanzati (SISSA) in Trieste, have recently published a paper entitled Synonymous Mutations Reduce Genome Compactness in Icosahedral ssRNA Viruses in the latest issue of Biophysical Journal (108 194–202 2015). The paper discusses the effect of synonymous mutations – mutations that do not change the protein complement – on the size of the folded RNA molecule, proving that even a very restricted phase space of synonymous mutations is still rich enough to support variations in the size of the RNA. The paper was also featured on the cover of the journal and commented on in the “New & Notable” section of the journal by A. Ben-Shaul and W.M. Gelbarta, "Viral ssRNAs Are Indeed Compact”. The paper was also featured on the blog phys.org as well as several other science news outlets.


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Liquid crystal elastomers are promising for building actuators due to their excellent thermomechanical response, but it is challenging to manufacture them additively. Members of the Solid State Department (F5) of Jožef Stefan Institute, A. Rešetič, J. Milavec, B. Zupančič, B. Zalar and V. Domenici from Italy have shown that limitations imposed by the synthesis of liquid crystal elastomers can be overcome by doping microparticles to the polymer matrix and curing the composite resin in external magnetic field. The new composite material provides for conventional moulding of elastic objects of general shapes and thermomechanical deformation modes. This work has been published in an article Polymer-dispersed liquid crystal elastomers in Nature Communications.


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Revija Nature Communications je 12. junija 2015 objavila članek z naslovom Spin-stripe phase in a frustrated zigzag spin-1/2 chain, ki so ga napisali Matej Pregelj, Andrej Zorko in Denis Arčon z Odseka za fiziko trdne snovi Instituta “Jožef Stefan” v sodelovanju s partnerji iz Švice, Francije in Japonske. Delo razkriva spojino beta-TeVO4 kot nov modelski sistem frustrirane spinske verige. Glavni rezultat je odkritje nanometrske modulacije magnetne strukture (angl. stripe phase) na prehodu med spiralno in kolinearno magnetno ureditvijo. V nasprotju s prej znanimi moduliranimi elektronskimi strukturami se v tem primeru pasovi pojavijo kljub odsotnosti interakcij dolgega dosega. Predstavljeni sistem odpira možnosti za boljše razumevanja analognih nanometrsko moduliranih ureditev v drugih sistemih, npr. visokotemperaturnih superprevodnikih.


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Raziskovalci z Odseka za fiziko trdne snovi Denis Arčon, Peter Jeglič in Anton Potočnik so pomembno prispevali k odkritju novega kovinskega stanja snovi v superprevodnih materialih na osnovi molekul C60. V obširni mednarodni raziskavi so novo stanje odkrili pri sistematičnem spreminjanju razdalje med sosednjimi molekulami C60 preko dopiranja osnovnega materiala Cs3C60 z rubidijem. Študija je razkrila izredno bogat fazni diagram, kjer se prepletajo izolatorska, magnetna, kovinska in superprevodna stanja, vključno z doslej neznanim stanjem, ki so ga raziskovalci poimenovali »Jahn-Tellerjeva kovina«. Članek je bil nedavno objavljen v Science Advances, ki je nova znanstvena revija skupine AAAS (Science) in je bil takoj opažen na številnih spletnih portalih, vključno s physicsworld.com.


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Revija Advanced Functional Materials je 15. 5. 2015 objavila članek z naslovom Controllable Broadband Absorption in the Mixed Phase of Metamagnets, ki so ga napisali Matej Pregelj, Andrej Zorko in Matjaž Gomilšek z Odseka za fiziko trdne snovi Instituta "Jožef Stefan" s partnerji iz Švice, Nemčije in Moldavije. Članek razkriva, da metamagnetni materiali absorbirajo elektromagnetno valovanje v izjemno širokem frekvenčnem območju. Efekt krmili zunanje magnetno polje, ki aktivira mešano fero/antiferomagnetno fazo, kjer se absorpcija v sistemu Cu3Bi(SeO3)2O2Br razteza vsaj preko devetih velikostnih frekvenčnih razredov. Ob dejstvu, da je v umetnih metamagnetnih materialih (tankih magnetnih plasteh) mogoče »nastaviti« krmilno magnetno polje, omenjen pojav razkriva možnost direktnega uravnavanja novih funkcionalnih lastnosti teh materialov.


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Sodelavci Odseka za elektronsko keramiko Instituta »Jožef Stefan« doc. dr. Tadej Rojac, dr. Hana Uršič, doc. dr. Andreja Benčan in prof. dr. Barbara Malič so v sodelovanju s prof. dr. Draganom Damjanovićem iz Swiss Federal Institute of Technology v aprilski številki revije Advanced Functional Materials (faktor vpliva IF 10,4) objavili članek z naslovom »Mobile Domain Walls as a Bridge between Nanoscale Conductivity and Macroscopic Electromechanical Response«. Avtorji so na primeru polikristaliničnega BiFeO3 dokazali, da lokalna prevodnost domenskih sten v zrnih pomembno vpliva na povprečni, makroskopski, piezoelektrični odziv keramike in jo torej moramo upoštevati pri interpretaciji in kontroli elektro-mehanskih lastnosti piezoelektrične keramike. Članek je bil pospremljen tudi z notranjo naslovnico revije.


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V Laboratoriju za hladne atome odseka za Fiziko trdne snovi Instituta "Jožef Stefan", ki se na Reaktorskem centru postavlja v sodelovanju z odsekoma za Teoretično fiziko ter Fiziko nizkih in srednjih energij, so prvič ujeli in ohladili atome cezija. Na sliki je pogled skozi okno vakuumske komore, kjer lebdi 50 milijonov cezijevih atomov s temperaturo nekaj 100 mikrokelvinov, ki jih zaradi fluorescenčne svetlobe vidimo kot majhno rožnato kroglico. V teku so že priprave na naslednji pomemben korak, kjer se bodo atomi z uporabo močne laserske svetlobe ujeli v dipolno past in s procesom izparevanja ohladili na temperaturo pod 50 nanokelvinov, ki ustreza temperaturi prehoda v Bose-Einsteinov kondenzat. Več informacij o metodah laserskega hlajenja in lovljenja atomov je na voljo na ultracool.ijs.si.


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V članku, ki je izšel v reviji Nature Physics, je prof. dr. J. Bonča s podoktorskima študentoma dr. L. Vidmarjem in dr. D. Goležem z Odseka za teoretično fiziko Instituta preučeval ultrahitro dinamiko elektronov v nekaterih visokotemperaturnih superprevodnikih, še posebej izvor privlačne sklopitve med nosilci naboja ter velikost njene časovne zakasnitve. Določitev te je eksperimentalno izjemno zahtevna. Z izvirno numerično metodo so avtorji pokazali, da fotovzbujen nosilec naboja relaksira preko sklopitve z lokalnimi antiferomagnetnimi ekscitacijami v približno 10 fs, kar se ujema z eksperimenti. Po analogiji s klasično fotografijo so avtorji sestavili "počasen posnetek" elektronske kvantne dinamike. Odkritje omogoča bolj podroben vpogled v časovno dinamiko kupratov na ultrahitri časovni skali in pomeni nov mejnik v razumevanju mehanizma visokotemperaturne superprevodnosti.


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Spojine s srebrom v oksidacijskem stanju +2 imajo številne nenavadne fizikalno-kemijske lastnosti, ki so opisane v preglednem članku "Chemistry of Silver(II): a Cornucopia of Peculiarities". Članek, ki sta ga napisala Wojciech Grochala (Univerza v Varšavi) in Zoran Mazej (Institut »Jožef Stefan«), je izšel v reviji Philosophical Transactions A. Revijo izdaja Kraljeva družba iz Londona in je nastarejša revija na svetu, ki je namenjena izključno znanosti. Izhajati je začela leta 1665 in letos praznuje 350-letnico svojega obstoja. Vsaka posamezna številka je samostojen tematski sklop. Številka, v kateri je izšel omenjeni prispevek, nosi naslov "The new chemistry of the elements" in je namenjena pomenu periodnega sistema.


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Revija PNAS je ob 100. obletnici izhajanja objavila članek Knot theory realizations in nematic colloids, ki so ga napisali Simon Čopar, Uroš Tkalec, Igor Muševič in Slobodan Žumer s Fakultete za matematiko in fiziko v Ljubljani, Fakultete za naravoslovje in matematiko v Mariboru in Odseka za fiziko trdne snovi Instituta "Jožef Stefan". Avtorji poročajo o uporabi različnih načinov iz teorije vozlov na zavozlanih defektnih strukturah v tekočekristalnih koloidih. Z eksperimenti lahko razkrijemo številne podrobnosti teoretičnih algoritmov, najdemo bližnjice do konstrukcije grafov in ograjenih površin neposredno iz mikroskopskih posnetkov in identificiramo vozle brez uporabe numeričnih simulacij. Delo je primer vzajemne povezanosti fizikalnih konceptov z matematično teorijo, kjer abstraktna topologija zaživi v eksperimentu.


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Dr. Marko Soderžnik, sodelavec Odseka za nanostrukturne materiale je v okviru evropskega projekta »Replacement and Original Magnet Engineering Options« - ROMEO (koordinatorka prof. dr. Spomenka Kobe) odločilno prispeval k uspehu projekta. Raziskave, ki so bile osnova za visoko inovativno tehnologijo, razvito na odseku, in ki temelji na elektroforetski depoziciji in posebnem mehanizmu difuzije po mejah med zrni magnetnega materiala, so prispevale k temu, da so bile dosežene lastnosti, ki so končni cilj projekta. To tehnologijo zdaj skupaj s sodelavci iz nemškega Vacuumschmelze preizkušajo na pilotni liniji v Hanauu. Končni rezultat so visokoenergijski magneti z minimalno vsebnostjo dragocenih težkih redkih zemelj, ki so ključni element motorja vetrne elektrarne Siemens.


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Člana Odseka za teoretično fiziko Instituta "Jožef Stefan" Luca Tubiana in Rudolf Podgornik ter nekdanji sodelavec Anže Losdorfer Božič so skupaj s sodelavcem Christianom Michelettijem s SISSA v Trstu objavili članek "Synonymous Mutations Reduce Genome Compactness in Icosahedral ssRNA Viruses” v zadnji številki revije Biophysical Journal. V članku opisujejo svoje študije efekta sinonimnih mutacij, torej takšnih, ki ne spreminjajo proteinskega komplementa, na velikost virusne ssRNA in dokažejo, da je tudi močno zožen fazni prostor sinonimnih mutacij še vedno dovolj velik, da lahko privede do sprememb v velikosti zložene virusne RNA. Članek je bil predstavljen tudi na naslovnici revije in kot “featured article” s komentarjem A. Ben-Shaula in W. M. Gelbarta z naslovom "Viral ssRNAs Are Indeed Compact”. Članek je bil predstavljen tudi na blogu phys.org.


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Na avstrijskem inštitutu Joanneum Research je 21. januarja 2015 potekal FORUM ROBOTICS, kjer je na plenarnem predavanju z naslovom "Robots can learn!" direktor prof. dr. Jadran Lenarčič predstavil Institut "Jožef Stefan" ter najnovejše dosežke in vizijo razvoja robotike v svetu. Predavanja se je udeležil tudi član deželne vlade avstrijske Štajerske g. Christopher Drexler.
Sodelovanje med inštitutoma poteka na različnih področjih že od leta 2005, ko je bil podpisan dogovor o sodelovanju. Joanneum Research odpira nov oddelek robotike, ki bo v Celovcu in je za sodelovanje z Institutom "Jožef Stefan" še posebej zainteresiran. S tem se odpirajo tudi velike možnosti za skupne raziskovalne projekte in skupen nastop pri partnerjih v gospodarstvu na obeh straneh meje.


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Revija Nature Physics je 22. decembra 2014 objavila članek z naslovom Light-controlled topological charge in a nematic liquid crystal, ki so ga napisali Maryam Nikkhou, Miha Škarabot, Simon Čopar, Miha Ravnik, Slobodan Žumer in Igor Muševič, sodelavci odseka F5 Instituta "J. Stefan" in Fakultete za matematiko in fiziko Univerze v Ljubljani. Članek opisuje eksperimente, v katerih z močno lasersko svetlobo ustvarijo in stabilizirajo par topoloških defektov v tekočem kristalu, ki ga tvorita defekt in antidefekt oziroma »delec« in »antidelec«. Slika prikazuje tekoči kristal, kot ga vidimo pod mikroskopom le nekaj milisekund po laserskem impulzu. Tvori se gosta mreža topoloških defektov, iz katerih sčasoma nastanejo pari topoloških defektov, kar spominja na Kibble-Zurekov mehanizem produkcije monopolov v kozmologiji. Z uporabo teorije so določili dinamiko anihilacije in osnovna topološka pravila, po katerih se ravnajo opaženi mehanizmi produkcije topološkega naboja.


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Institut “Jožef Stefan” in francoski center CNRS sta 9. januarja 2015 podpisala dogovor o skupnem laboratoriju LIA. Glavna raziskovalna tematika novega laboratorija je področje kvazikristalov in kompleksnih zlitin z namenom poiskati odgovore na še nerešena, a temeljna vprašanja: kako in zakaj se pojavi kompleksnost, kaj je osnovni mehanizem za spodbujanje kompleksnosti, je ta mehanizem edinstven, v kakšni povezavi je z elektronsko in atomsko strukturo kristala in podobno. Laboratorij LIA ne bo prispeval le k boljšemu razumevanju razvoja kompleksnosti v kovinah, ki je na neki način še vedno na začetku, ampak bo tudi spodbuda za fizikalno metalurgijo na novih področjih znanja, povezanih s fiziko trdne snovi in anorganske kemije.