Research topics

Activities

Publications

Collaborations

Alumni

 

Research topics

Magnet-superconductor hybrid systems

 

Nano-scale heterogeneous systems consisting of magnetic and superconducting parts, such as quantum dots embedded in Josephson junctions, nanowires coated with a superconducting layer, or magnetic molecules adsorbed on superconductor surfaces, host long-lived excitations inside the gap (Yu-Shiba-Rusinov states, Andreev bound states). These excitations can be exploited in various quantum devices for quantum information storage and processing. We explore the basic physics of the sub-gap states, often in collaboration with leading experimental groups, and we develop novel theoretical tools required to tackle these strongly correlated problems.

 

dr. Rok Žitko

Luka Pavešić

 

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Phase diagrams of a quantum dot coupled to a superconducting island for different ratios of charging energy to superconducting gap, as a function of gate voltages applied to the dot and the island.

 

 

 

Electronic correlations in multi-orbital materials

 

Many materials are multi-orbital, that is, more than one active orbital is important. The Hund's rule coupling that splits atomic multiplet splittings has been found to importantly affect the strength of electronic correlations in a way that depends on the filling of the orbitals. Hund's rule coupling can cause strong correlations far from a Mott insulating state. Materials in which Hund's rule coupling is playing the key role, such as ruthenates and iron pnictides, are known as Hund's metals. With dynamical mean-field theory calculations we are investigating properties of this family of compounds.

 

dr. Denis Golež

dr. Jernej Mravlje

dr. Rok Žitko

 

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Electronic and spin-transport in bad metals

 

Many metals in which electronic correlations are important are bad, that is, their resisistivity exceeds the Mott-Ioffe-Regel value which corresponds to the resistivity a material has when the scattering events are so frequent that the electron mean-free path is equivalent to the lattice spacing. Using finite-temperature Lanzczos method, dynamical mean-field theory, and its cluster generalizations we are exploring the mechanism of electronic and spin transport in this regime.

 

Martin Ulaga

dr. Jure Kokalj

dr. Rok Žitko

dr. Jernej Mravlje

dr. Janez Bonča

dr. Peter Prelovšek

 

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Relaxaton dynamic of complex quantum systems

 

  • Relaxation of a photo-doped charge carrier in the spin background
  • Relaxation dynamics of the Holstein polaron 
  • Driven strongly correlated electron and electron-phonon coupled  systems  far from the equilibrium 

 

dr. Janez Bonča

dr. Denis Golež

dr. Lev Vidmar

dr. Peter Prelovšek

 

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From Phys. Rev. Lett. 106, 196401 (2011).

 

Finite - T properties of lattice polaron systems

 

  • Spectral properties of a charge coupled to various bosonic degrees of freedom
  • Thermalization of a highly excited charge carrier via lattice degrees of freedom

 

dr. Janez Bonča

dr. Lev Vidmar

 

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Holstein polaron spectral function. From Phys. Rev. B 100, 094307 (2019).

 

Static and dynamic properties of disordered complex quantum systems

 

  • Unusual properties of driven disordered quantum systems 
  • Dynamics of disordered systems coupled to various bosonic baths

 

dr. Janez Bonča

dr. Peter Prelovšek

 

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From Phys. Rev. Lett. 119, 246601 (2017).

 

Theory of quantum spin liquids

 

Quantum spin liquids are spin systems on frustrated lattices, which do not exhibit any magnetic long range order at low temperatures. Their existence and properties offer several challenges to theoreticians, also in connection with recent experiments on several classes of real spin-liquid materials. Our studies focus on relevant basic spin models, calculating numerically their finite-temperature thermodynamic and dynamical properties, also in close collaboration with experimental group at IJS.

 

dr. P. Prelovšek

dr. J. Kokalj

 

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Collective phenomena in complex systems and networks

 

Current research of complex systems focuses on their complex geometry, which may have evolved through evolutionary optimization that allows for new functional properties. Higher organized complexes are recognized as aggregates of simplexes (triangles, tetrahedra, and higher cliques) and can be described by algebraic topology methods. Beyond pairwise interactions, these simplicial complexes enable higher-order interactions based on geometry, which may be crucial for the emergence of new dynamical phenomena on networks. By combining the methods of Statistical physics with Graph theory and Algebraic topology of graphs we investigate:

  • Structure of simplicial complexes in brain networks based on the neuroimaging data from Human Connectome Project and Social neuroscience hyperscanning data;
  • Generative models for self-assembly of simplexes of different size under geometrical constraints, chemical affinity and the presence of defects;
  • Magnetisation-reversal processes on disordered nanonetworks with aggregated simplicial complexes and geometric spin frustrations;
  • Self-organised criticality mechanisms that underlie collective knowlegde creation in online social systems;
  • Agent-Based Modeling of SARS CoV-02 Epidemics simulations and analysis of stochastic bio-social processes;

 

dr. Bosiljka Tadić

dr. Raša Pirc

 

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Activities

Scientific meetings organized by the group

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Selected Publications

  • Emission of correlated jets from a driven matter-wave soliton in a quasi-one-dimensional geometry
    Tadej Mežnaršič, Rok Žitko, Tina Arh, Katja Gosar, Erik Zupanič, and Peter Jeglič
    Phys. Rev. A 101, 031601 (2020)
  • Large-scale influence of defect bonds in geometrically constrained self-assembly
    Bosiljka Tadic, Milovan Suvakov, Miroslav Andjelkovic, and Geoff J. Rodgers
    Phys. Rev. E 102, 032307 (2020)
  • Magnetisation Processes in Geometrically Frustrated Spin Networks with Self-Assembled Cliques
    Bosiljka Tadic, Miroslav Andjelkovic, Milovan Suvakov, and Geoff J. Rodgers
    Entropy 22, 336 (2020)
  • The topology of higher-order complexes associated with brain hubs in human connectomes
    M. Andjelkovic, B. Tadic, and R. Melnik
    Scientific Reports 10, 17320 (2020)
  • Resistivity and its fluctuations in disordered many-body systems: From chains to planes
    M. Mierzejewski, M. Środa, J. Herbrych, and P. Prelovšek
    Phys. Rev. B 102, 161111 (2020)
  • Superconductivity emerging upon Se doping of the quantum spin liquid $1T\text{\ensuremath{-}}{\mathrm{TaS}}_{2}$
    Izidor Benedičič, Nejc Janša, Marion van Midden, Peter Jeglič, Martin Klanjšek, Erik Zupanič, Zvonko Jagličić, Petra Šutar, Peter Prelovšek, Dragan Mihailovič, and Denis Arčon
    Phys. Rev. B 102, 054401 (2020)
  • Origin of Magnetic Ordering in a Structurally Perfect Quantum Kagome Antiferromagnet
    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
    Phys. Rev. Lett. 125, 027203 (2020)
  • Vanishing Wilson ratio as the hallmark of quantum spin-liquid models
    P. Prelovšek, K. Morita, T. Tohyama, and J. Herbrych
    Phys. Rev. Research 2, 023024 (2020)
  • Similarity of thermodynamic properties of the Heisenberg model on triangular and kagome lattices
    P. Prelovšek and J. Kokalj
    Phys. Rev. B 101, 075105 (2020)
  • Modeling latent infection transmissions through biosocial stochastic dynamics
    Bosiljka Tadic and Roderick Melnik
    PLOS ONE 15, 1 (2020)
  • Spectral function of the Holstein polaron at finite temperature
    J. Bonča, S. A. Trugman, and M. Berciu
    Phys. Rev. B 100, 094307 (2019)
  • Einstein Relation for a Driven Disordered Quantum Chain in the Subdiffusive Regime
    M. Mierzejewski, P. Prelovšek, and J. Bonča
    Phys. Rev. Lett. 122, 206601 (2019)
  • Functional Geometry of Human Connectomes
    B. Tadic, M. Andjelkovic, and R. Melnik
    Scientific Reports 9, 12060 (2019)
  • Spectral properties of hyperbolic nanonetworks with tunable aggregation of simplexes
    Marija Mitrovic Dankulov, Bosiljka Tadic, and Roderick Melnik
    Phys. Rev. E 100, 012309 (2019)
  • Mottness collapse without metallisation in the domain walls of triangular-lattice Mott insulator 1T-TaS2
    J. Skolimowski, Ya. Gerasimenko, and R. Žitko
    Phys. Rev. Lett. 122, 036802 (2019)
  • Kondo screening in a charge-insulating spinon metal
    M. Gomilšek, R. Žitko, M. Klanjšek, M. Pregelj, C. Baines, Y. Li, Q. M. Zhang, and A. Zorko
    Nature Phys. 15, 754 (2019)
  • Suppressed energy transport in the strongly disordered Hubbard chain
    Maciej Kozarzewski, Marcin Mierzejewski, and Peter Prelovšek
    Phys. Rev. B 99, 241113 (2019)
  • Einstein Relation for a Driven Disordered Quantum Chain in the Subdiffusive Regime
    M. Mierzejewski, P. Prelovšek, and J. Bonča
    Phys. Rev. Lett. 122, 206601 (2019)
  • Instability of subdiffusive spin dynamics in strongly disordered Hubbard chain
    M. Środa, P. Prelovšek, and M. Mierzejewski
    Phys. Rev. B 99, 121110 (2019)
  • Hidden geometries in networks arising from cooperative self-assembly
    M. Suvakov, M. Andjelkovic, and B. Tadic
    Scientific Reports 8, 1987 (2018)
  • {Yu-Shiba-Rusinov} screening of spins in double quantum dots
    K. Grove-Rasmussen, G. Steffensen, A. Jellinggaard, M. H. Madsen, R. Žitko, J. Paaske, and J. Nygård
    Nat. Commun. 9, 2376 (2018)
  • Supercurrent in a Double Quantum Dot
    J. C. Estrada Saldaña, A. Vekris, G. Steffensen, R. Žitko, P. Krogstrup, J. Paaske, K. Grove-Rasmussen, and J. Nygård
    Phys. Rev. Lett. 121, 257701 (2018)
  • Transient and persistent particle subdiffusion in a disordered chain coupled to bosons
    P. Prelovšek, J. Bonča, and M. Mierzejewski
    Phys. Rev. B 98, 125119 (2018)
  • Finite-temperature properties of the extended Heisenberg model on a triangular lattice
    P. Prelovšek and J. Kokalj
    Phys. Rev. B 98, 035107 (2018)
  • Spin Subdiffusion in the Disordered Hubbard Chain
    Maciej Kozarzewski, Peter Prelovšek, and Marcin Mierzejewski
    Phys. Rev. Lett. 120, 246602 (2018)
  • Counting local integrals of motion in disordered spinless-fermion and Hubbard chains
    Marcin Mierzejewski, Maciej Kozarzewski, and Peter Prelovšek
    Phys. Rev. B 97, 064204 (2018)
  • Reduced-basis approach to many-body localization
    P. Prelovšek, O. S. Barišić, and M. Mierzejewski
    Phys. Rev. B 97, 035104 (2018)
  • Complete Many-Body Localization in the $t\text{\ensuremath{-}}J$ Model Caused by a Random Magnetic Field
    Gal Lemut, Marcin Mierzejewski, and Janez Bonča
    Phys. Rev. Lett. 119, 246601 (2017)
  • Mechanisms of self-organized criticality in social processes of knowledge creation
    Bosiljka Tadic, Marija Mitrovic Dankulov, and Roderick Melnik
    Phys. Rev. E 96, 032307 (2017)
  • Self-consistent approach to many-body localization and subdiffusion
    P. Prelovšek and J. Herbrych
    Phys. Rev. B 96, 035130 (2017)
  • Density correlations and transport in models of many-body localization
    P. Prelovsek, M. Mierzejewski, O. Barisic, and J. Herbrych
    Annalen der Physik 1600362, 1 (2017)
  • A high-temperature quantum spin liquid with polaron spins
    Martin Klanjšek, Andrej Zorko, Rok Žitko, Jernej Mravlje, Zvonko Jagličić, Pabitra Kumar Biswas, Peter Prelovšek, Dragan Mihailovic, and Denis Arčon
    Nature Physics 13, 1130 (2017)
  • Nature of Bosonic Excitations Revealed by High-Energy Charge Carriers
    Jan Kogoj, Marcin Mierzejewski, and Janez Bonča
    Phys. Rev. Lett. 117, 227002 (2016)
  • Algebraic Topology of Multi-Brain Connectivity Networks Reveals Dissimilarity in Functional Patterns during Spoken Communications
    Bosiljka Tadic, Miroslav Andjelkovic, Biljana Mileva Boshkoska, and Zoran Levnajic
    PLOS ONE 11, 1 (2016)
  • Universal dynamics of density correlations at the transition to the many-body localized state
    M. Mierzejewski, J. Herbrych, and P. Prelovšek
    Phys. Rev. B 94, 224207 (2016)
  • Absence of full many-body localization in the disordered Hubbard chain
    P. Prelovšek, O. S. Barišić, and M. Žnidarič
    Phys. Rev. B 94, 241104 (2016)
  • Decay of density waves in coupled one-dimensional many-body-localized systems
    Peter Prelovšek
    Phys. Rev. B 94, 144204 (2016)
  • Dynamical conductivity and its fluctuations along the crossover to many-body localization
    Osor S. Barišić, Jure Kokalj, Ivan Balog, and Peter Prelovšek
    Phys. Rev. B 94, 045126 (2016)
  • Distinctive response of many-body localized systems to a strong electric field
    Maciej Kozarzewski, Peter Prelovšek, and Marcin Mierzejewski
    Phys. Rev. B 93, 235151 (2016)
  • Snapshots of the retarded interaction of charge carriers with ultrafast fluctuations in cuprates
    S. Dal Conte, L. Vidmar, D. Golež, M. Mierzejewski, G. Soavi, S. Peli, F. Banfi, G. Ferrini, R. Comin, B. M. Ludbrook, L. Chauviere, N. D. Zhigadlo, H. Eisaki, M. Greven, S. Lupi, A. Damascelli, D. Brida, M. Capone, J. Bonča, G. Cerullo, and C. Giannetti
    Nature Physics 11, 421 (2015)
  • Holon-doublon binding as the mechanism for the Mott transition
    Peter Prelovšek, Jure Kokalj, Zala Lenarčič, and Ross H. McKenzie
    Phys. Rev. B 92, 235155 (2015)
  • Approximate conservation laws in perturbed integrable lattice models
    Marcin Mierzejewski, Tomaž Prosen, and Peter Prelovšek
    Phys. Rev. B 92, 195121 (2015)
  • Exciton recombination in one-dimensional organic Mott insulators
    Zala Lenarčič, Martin Eckstein, and Peter Prelovšek
    Phys. Rev. B 92, 201104 (2015)
  • Spin and thermal conductivity in a classical disordered spin chain
    B. Jenčič and P. Prelovšek
    Phys. Rev. B 92, 134305 (2015)
  • Antiferromagnetic order in weakly coupled random spin chains
    J. Kokalj, J. Herbrych, A. Zheludev, and P. Prelovšek
    Phys. Rev. B 91, 155147 (2015)
  • Identifying Local and Quasilocal Conserved Quantities in Integrable Systems
    Marcin Mierzejewski, Peter Prelovšek, and Tomaž Prosen
    Phys. Rev. Lett. 114, 140601 (2015)
  • Charge recombination in undoped cuprates
    Zala Lenarčič and Peter Prelovšek
    Phys. Rev. B 90, 235136 (2014)
  • Energy and particle currents in a driven integrable system
    D. Crivelli, P. Prelovšek, and M. Mierzejewski
    Phys. Rev. B 90, 195119 (2014)
  • Memory function approach to in-plane anisotropic resistivity in the antiferromagnetic phase of iron arsenide superconductors
    Koudai Sugimoto, Peter Prelovšek, Eiji Kaneshita, and Takami Tohyama
    Phys. Rev. B 90, 125157 (2014)
  • Multistage dynamics of the spin-lattice polaron formation
    Jan Kogoj, Zala Lenarčič, Denis Golež, Marcin Mierzejewski, Peter Prelovšek, and Janez Bonča
    Phys. Rev. B 90, 125104 (2014)
  • Peltier effect in strongly driven quantum wires
    M. Mierzejewski, D. Crivelli, and P. Prelovšek
    Phys. Rev. B 90, 075124 (2014)
  • Breakdown of the Generalized Gibbs Ensemble for Current-Generating Quenches
    Marcin Mierzejewski, Peter Prelovšek, and Tomaž Prosen
    Phys. Rev. Lett. 113, 020602 (2014)
  • Effective $S=\frac{1}{2}$ description of the $S=1$ chain with strong easy-plane anisotropy
    C. Psaroudaki, J. Herbrych, J. Karadamoglou, P. Prelovšek, X. Zotos, and N. Papanicolaou
    Phys. Rev. B 89, 224418 (2014)
  • Optical response of highly excited particles in a strongly correlated system
    Zala Lenarčič, Denis Golež, Janez Bonča, and Peter Prelovšek
    Phys. Rev. B 89, 125123 (2014)
  • Co-Evolutionary Mechanisms of Emotional Bursts in Online Social Dynamics and Networks
    Bosiljka Tadic, Vladimir Gligorijevic, Marija Mitrovic, and Milovan Suvakov
    Entropy 15, 5084 (2013)
  • Local Spin Relaxation within the Random Heisenberg Chain
    J. Herbrych, J. Kokalj, and P. Prelovšek
    Phys. Rev. Lett. 111, 147203 (2013)
  • Ultrafast Charge Recombination in a Photoexcited Mott-Hubbard Insulator
    Zala Lenarčič and Peter Prelovšek
    Phys. Rev. Lett. 111, 016401 (2013)
  • Eigenvalue Statistics of Reduced Density Matrix during Driving and Relaxation
    M. Mierzejewski, T. Prosen, D. Crivelli, and P. Prelovšek
    Phys. Rev. Lett. 110, 200602 (2013)
  • Eigenstate thermalization within isolated spin-chain systems
    R. Steinigeweg, J. Herbrych, and P. Prelovšek
    Phys. Rev. E 87, 012118 (2013)
  • Relaxation Dynamics of the Holstein Polaron
    Denis Golež, Janez Bonča, Lev Vidmar, and Stuart A. Trugman
    Phys. Rev. Lett. 109, 236402 (2012)
  • Spin hydrodynamics in the $S=\frac{1}{2}$ anisotropic Heisenberg chain
    J. Herbrych, R. Steinigeweg, and P. Prelovšek
    Phys. Rev. B 86, 115106 (2012)
  • Coexistence of anomalous and normal diffusion in integrable Mott insulators
    R. Steinigeweg, J. Herbrych, P. Prelovšek, and M. Mierzejewski
    Phys. Rev. B 85, 214409 (2012)
  • Dielectric Breakdown in Spin-Polarized Mott Insulator
    Zala Lenarčič and Peter Prelovšek
    Phys. Rev. Lett. 108, 196401 (2012)
  • Quantitative analysis of bloggers' collective behavior powered by emotions
    Marija Mitrovic, Georgios Paltoglou, and Bosiljka Tadic
    Journal of Statistical Mechanics: Theory and Experiment 2011, P02005 (2011)
  • Finite-temperature Drude weight within the anisotropic Heisenberg chain
    J. Herbrych, P. Prelovšek, and X. Zotos
    Phys. Rev. B 84, 155125 (2011)
  • Integrable Mott Insulators Driven by a Finite Electric Field
    Marcin Mierzejewski, Janez Bonča, and Peter Prelovšek
    Phys. Rev. Lett. 107, 126601 (2011)
  • Nonequilibrium Quantum Dynamics of a Charge Carrier Doped into a Mott Insulator
    M. Mierzejewski, L. Vidmar, J. Bonča, and P. Prelovšek
    Phys. Rev. Lett. 106, 196401 (2011)
  • Nonequilibrium dynamics of the Holstein polaron driven by an external electric field
    Lev Vidmar, Janez Bonča, Marcin Mierzejewski, Peter Prelovšek, and Stuart A. Trugman
    Phys. Rev. B 83, 134301 (2011)
  • Modeling collective charge transport in nanoparticle assemblies
    Milovan Suvakov and Bosiljka Tadic
    Journal of Physics: Condensed Matter 22, 163201 (2010)
  • Nonlinear Current Response of an Isolated System of Interacting Fermions
    Marcin Mierzejewski and Peter Prelovšek
    Phys. Rev. Lett. 105, 186405 (2010)
  • Conductivity in a disordered one-dimensional system of interacting fermions
    O. S. Barišić and P. Prelovšek
    Phys. Rev. B 82, 161106 (2010)
  • Dynamical central peak and spinon deconfinement in frustrated spin chains
    J. Kokalj and P. Prelovšek
    Phys. Rev. B 82, 060406 (2010)
  • Thermal transport in a spin-$\frac{1}{2}$ Heisenberg chain coupled to a magnetic or nonmagnetic impurity
    A. Metavitsiadis, X. Zotos, O. S. Barišić, and P. Prelovšek
    Phys. Rev. B 81, 205101 (2010)
  • Phenomenological theory of the anomalous normal-state transport properties of iron pnictides
    P. Prelovšek and I. Sega
    Phys. Rev. B 81, 115121 (2010)

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Selected Collaborations

  • S. A. Trugman, Center for Integrated Nano technologies, Los Alamos National Laboratory, NM USA
  • T. Tohyama, Tokyo University of Science, Tokyo, Japan
  • M. Mierzejewski, Department of Theoretical Physics, Faculty of Fundamental Problems of Technology, Wrocław University of Science and Technology
  • J. C. Estrada Saldaña, J. Paaske, K. Grove-Rasmussen, J. Nygård, QDev, Center for quantum devices, University of Copenhagen, Denmark
  • J. Vučičević, D. Tanasković, Institute of Physics, Belgrade, Serbia
  • B. S. Shastry, University of California Santa Cruz, USA
  • M. Fabrizio, SISSA, Trieste, Italy
  • R. Melnik, Department of Mathematics, Wilfrid Laurier University, Waterloo, ON, Canada
  • M. Mitrović Dankulov, Scientific Computing Lab, Institute of Physics, Belgrade, Serbia
  • G. J. Rodgers, Brunel University London, UK
  • M. Šuvakov, Institute of Physics, Belgrade, Serbia and Mayo Clinics, Rochester, USA
  • S. Thurner, Medical University Vienna and Complexity Science Hub Vienna, Austria

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Alumni and former associates (subsequent affiliation)

  • Kristjan Haule (Rutgers University)
  • Matjaž Zemljič (Banka Slovenije)
  • Janez Jaklič (Cadence Design Systems, Inc.)

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The group is funded in part by the Slovenian Research Agency (research core funding No. P1-0044).