2022 Science Impact Award awarded to Andrej Zorko

Andrej Zorko is the recipient of the 2022 Science Impact Award for “the first realization of a quantum spin liquid on a triangular spin lattice with dominant Ising antiferromagnetic exchange interaction using WISH, MARI, and MUSR”. This award is given annually by the Science and Technology Facilities Council from the United Kingdom to celebrate the scientific impact of the research conducted at the large-scale user facility ISIS Neutron and Muon Source in the last five years. This is a world-leading research center that supports more than 2000 researchers applying neutron scattering and muon spectroscopy to various fields of natural sciences. Andrej Zorko led an international research group and was awarded for their discovery of the first realization of a quantum spin liquid on a triangular spin lattice with dominant Ising antiferromagnetic exchange interactions, which has recently been published in Nature Materials. These results revealed that the family of rare-earth heptatantalates represents a novel framework for quantum spin liquids.

Read more about the achievement here!

A paper on the Ising quantum spin liquid on a triangular lattice published in Nature Materials

The Ising triangular-lattice antiferromagnet neodymium heptatantalate as a quantum spin liquid candidate

Nature Materials 21, 416 (2022)

In collaboration with researchers from the Institute of Mathematics, Physics and Mechanics and research institutions from India, the UK, France and the US, we discovered the first realization of a quantum spin liquid on a triangular spin lattice with dominant Ising antiferromagntic exchange interaction. An extensive experimental study was conducted, showing the absence of magnetic ordering and proving the existence of Ising-type spin correlations in neodymium heptatantalate NdTa7O19 at temperatures of only a few tens of millikelvins. The discovery of the Ising spin liquid introduces a new type of this enigmatic quantum entangled state of matter that remains dynamical down to the lowest temperatures. These results are published in the paper entitled The Ising triangular-lattice antiferromagnet neodymium heptatantalate as a quantum spin liquid candidate in the esteemed Nature Materials journal.

Full text of the paper can be found here.

Postdoc position in NV center magnetometry for solid state physics

Quantum Materials group is looking for a postdoctoral candidate to work on a project on nitrogen vacancy (NV) center magnetometry, in which we are developing a low-temperature probe based on diamond NV centers with a specific aim to address condensed-matter problems of unconventional superconductivity.

In 2022, we are integrating NV magnetometry with a low-temperature cryostat targeting the low-temperature physics of quantum materials. In this project, we would like to apply NV centers as a probe to investigate vortices in type-II superconductors, e.g. iron-pnictide or alkali-doped fulleride superconductors.

The candidate will be fully involved in the instrumentation development, optimization, and studies of target quantum materials. The position is initially open for the period from 1. 1. 2022 to 31. 12. 2024.

Contact: Prof. Denis Arčon

More information: Post-doc NV magnetometry

A paper on magnetic ordering of a kagome antiferromagnet published in Physical Review Letters

Origin of Magnetic Ordering in a Structurally Perfect Quantum Kagome Antiferromagnet
Phys. Rev. Lett. 125, 027203 (2020)

In collaboration with prof. Peter Prelovšek from the Department of Theoretical Physics and researchers from United Kingdom, USA and China, we have published a paper entitled “Origin of Magnetic Ordering in a Structurally Perfect Quantum Kagome Antiferromagnet” in Physical Review Letters.

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A paper on skyrmion dynamics under chemical substitution published in Physical Review Research as a Rapid Communication

Magnetism and Néel skyrmion dynamics in GaV4S8−ySey
Phys. Rev. Research 2, 032001(R) (2020)

A skyrmion lattice with a single muon spin

A team of researchers from the United Kingdom and Slovenia has published a paper in Physical Review Research as a Rapid Communication. The paper co-authored by Matjaž Gomilšek explores the influence of low levels of chemical substitution on the magnetism in GaV4S8−ySey.

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Matjaž Gomilšek wins the Jožef Stefan Golden Emblem Prize for an outstanding PhD thesis

Each year at the end of March the Jožef Stefan Institute awards the Jožef Stefan Golden Emblem Prizes for winning PhD dissertations in the fields of natural sciences, medicine and biotechnology. This year, one of three awarded works is the PhD thesis of Dr. Matjaž Gomilšek, entitled “Quantum Spin Liquids on Geometrically Frustrated Kagome Lattices“.

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Two recent arXiv preprint submissions

We have recently submitted two preprints to arXiv. We cordially invite you to read them and send any comments!

T. Arh, M. Gomilšek, P. Prelovšek, M. Pregelj, M. Klanjšek, A. Ozarowski, S. J. Clark, T. Lancaster, W. Sun, J.-X. Mi, and A. Zorko, The Origin of Magnetic Ordering in a Structurally-Perfect Quantum Kagome Antiferromagnet, arXiv:1912.09047 (submitted on 19 Dec 2019)

Ž. Gosar, N. Janša, T. Arh, P. Jeglič, M. Klanjšek, H. F. Zhai, B. Lv, and D. Arčon, Superconductivity in the regime of attractive interactions in the Tomonaga-Luttinger liquid, arXiv:2001.07909 (submitted on 22 Jan 2020)

A paper by T. Knaflič et al. published in PRB as an Editor’s suggestion

Spin-dimer ground state driven by consecutive charge and orbital ordering transitions in the anionic mixed-valence compound Rb4O6

Phys. Rev. B 101, 024419 (2020)

A new paper by T. Knaflič, P. Jeglič, M. Komelj, A. Zorko, P. K. Biswas, A. N. Ponomaryov, S. A. Zvyagin, M. Reehuis, A. Hoser, M. Geiß, J. Janek, P. Adler, C. Felser, M. Jansen, and D. Arčon has been published as an Editor’s suggestion in Physical Review B.

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Prof. Denis Arčon awarded the national Zois Prize

Prof. Denis Arčon (third from the left) receiving the Zois award. Photo credit: Marjan Verč, IJS

On November 20, 2019, the Republic of Slovenia awarded the highest prizes and awards for outstanding achievements in science, research and development to 18 top scientists. Among them, professor dr. Denis Arčon received the Žiga Zois Prize for outstanding achievements in the fields of quantum magnetism and unusual superconductivity.


The first Blinc Award for extraordinary achievement awarded to Martin Klanjšek

Martin Klanjšek was awarded the Blinc Award for extraordinary one-time achievement in physics for proving the existence of unusual quasiparticles called anyons.

Martin Klanjšek receiving the Blinc Award. Photo credit: Jan Šuntajs

On October 24, 2019, the Faculty of Mathematics and Physics of the University of Ljubljana and the Jožef Stefan Institute awarded the first Blinc awards for research and theoretical work in physics. The awards were founded to celebrate the best Slovenian physicists and to commemorate academician Robert Blinc, one of the sharpest Slovenian researchers and a member of the Slovenian Academy of Science and Arts.

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