# Conferences

## Conferences & Schools

 Quantum Information Entropy in PhysicsParticipant, 22/03/2022 - 25/03/2022Yukawa Institute for Theoretical Physics, Kyoto UniversityWebsite Ergodicity Breaking and Anomalous Transport in Quantum Many-Body SystemsSpeaker, 04/10/2021 - 08/10/2021MPI-PKS, Dresden, GermanyWebsite KITP Conference: Non-Equilibrium Universality in Many-Body PhysicsParticipant, 27/09/2021 - 30/09/2021Kavli Institute for Theoretical Physics, University of California, Santa Barbara, USWebsite Modern Developments in Quantum ChaosSpeaker, 20/09/2021 - 24/09/2021Physikzentrum Bad HonnefWebsite Condensed Matter Physics in the City: Online 2021Speaker, 28/06/2021 - 09/07/2021Hubbard Theory ConsortiumWebsite Theory of Condensed Matter 2021Participant, 10/06/2021University of WarwickWebsite Online Workshop: Entanglement in Strongly Correlated SystemsParticipant, 15/02/2021 - 26/02/2021Organised by Centro de Ciencias de Benasque Pedro PascualWebsite Virtual Meeting: New perspectives on quantum many-body chaosParticipant, 08/02/2021 - 11/02/2021Organised by the Royal SocietyWebsite Virtual Meeting: Many-Body Physics in Open Quantum SystemsParticipant, 21/01/2021 - 29/01/2021Organised by Princeton Center for Theoretical ScienceWebsite Virtual Conference: Frontiers of Quantum Computing and Quantum DynamicsParticipant, 19/10/2020 - 20/10/2020Organised by Kavli Institute for Theoretical Physics, University of California, Santa Barbara, USWebsite Virtual Workshop: Dynamics, criticality, and universality in random quantum circuitsParticipant, 30/09/2020 - 02/10/2020Organised by MPI-PKS, Dresden, GermanyWebsite Virtual Workshop: Fundamental Aspects of Statistical Mechanics and the Emergence of Thermodynamics in Non-Equilibrium SystemsSpeaker, 21/09/2020 - 23/09/2020Organised by DFG Research Unit FOR2692, Germany (Bielefeld University, Forschungszentrum Jülich, Oldenburg University, and Osnabrück University)Program and list of abstracts: HERE.Website Virtual Conference: Localisation 2020Speaker, 24/08/2020 - 29/08/2020Organised by Hokkaido University, JapanTopics:Anderson localization & transitionTopological insulators2D metal-insulator transition & electron interactionMany body-localisationInteger quantum Hall systemsNon-Hermitian systemsCold atomsWeyl semimetalsTalk: Measurement-induced transition in random quantum circuits: from stroboscopic to continuousM. Szyniszewski, A. Romito, H. SchomerusWebsite Virtual International Workshop: Real-time Dynamics in Strongly Correlated Quantum MatterParticipant, 08/04/2020 - 09/04/2020Organised by MPI-PKS, Dresden, GermanyWebsite Online workshop: Many-body physics out of equilibriumParticipant, 24/03/2020Organised by MPI-PKS, Dresden, GermanyWebsite Physics by the Lake 2019Tutor & presenter, 12/08/2019 - 16/08/2019Venue: The University of Stirling, Stirling, UKTalk: Localisation, ergodicity, and quantum measurementsWebsite Topological Quantum Matter: From Low-Temperature Physics to Non-Equilibrium DynamicsParticipant, 05/08/2019 - 09/08/2019Venue: Nordita, StockholmTalk: Entanglement transition from variable-strength weak measurementsM. Szyniszewski, A. Romito, H. SchomerusWebsite School and Conference on Complex Quantum Systems out of Equilibrium in Many-Body Physics and BeyondParticipant, 27/05/2019 - 07/06/2019Venue: Yerevan State University, Yerevan, ArmeniaWebsite Conference on Quantum Measurement: Fundamentals, Twists, and ApplicationsParticipant, 29/04/2019 - 04/05/2019Venue: ICTP, Trieste, ItalyTopics:Foundations of quantum mechanicsQuantum measurement in information processingQuantum measurements in nanodevicesQuantum measurement and thermodynamicsQuantum metrology and precision measurementsWebsite Summer School on Collective Behaviour in Quantum MatterParticipant, 27/08/2018 - 14/09/2018Venue: ICTP, Trieste, ItalyTopics:1. Statistical Mechanics: from foundations to quantum information.2. Numerical methods: high-level programming and advanced numerical methods.3. Coherent dynamics: entanglement, decoherence, phase transitions, driven systems.4. Topological quantum matter: phases and diagnostics.5. Physical implementations: cold atoms, trapped ions, nanophysics, materials.Lecturers:F. Alet (CNRS, Toulouse, France)E. Andrei (Rutgers University, US)B. Beri (University of Cambridge, UK)I. Bloch (MPQ, Garching, Germany)P. Calabrese (SISSA, Trieste, Italy)J. Chalker (University of Oxford, UK)X. Chen (Caltech, US)J. Dalibard (College de France, Paris, France)M. Devoret (Yale University, US)D. Dhar (Indian Institute of Science Education and Research, Pune)M. Heyl (MPIPKS Dresden, Germany)V. Khemani (Harvard University, US)W. Krauth (Ecole Normale Superieure, Paris, France)B. Lake (Berlin Technical University, Germany)C. Laumann (Boston University, US)A. Lazarides (MPIPKS Dresden, Germany)A. MacKenzie (MPI-CPfS Dresden, Germany)E. Martinez (University of Copenhagen, Denmark)U. Schollwoeck (LMU Munich, Germany)M. Znidaric (University of Ljubljana, Slovenia)Website Lancaster Probability Days 2018Participant, 22/05/2018 - 24/05/2018Venue: Postgraduate Statistics Centre, Lancaster, UKTopics:Modern Applications of Random PermutationsRandom Matrices and Quantum SymmetriesApplications of Probability in Statistical Learning TheoryWebsite Topological Matter in Artificial Gauge FieldsParticipant, 26/02/2018 - 02/03/2018Venue: Max Planck Institute for the Physics of Complex Systems, Dresden, GermanyTopics:Floquet engineering (Andre Eckardt)Topological order and anyons (Belen Paredes)Chern numbers counted in a synthetic-dimension quantum Hall strip (Ian B. Spielman)Realization of gauge fields in quantum gases (Ian B. Spielman)Topological insulators (Jan Carl Budich)Experimental realization of Chern insulators / Gauge fields in optical lattices (Monika Aidelsburger)Floquet topological insulators in photonic wave-guides (Alexander Szameit)Fractional Chern insulators and Methods (Frank Pollmann)Floquet states of irradiated electrons in topological solid-state systems (Fahad Mahmood)Website 2017 Arnold Sommerfeld School: Numerical methods for correlated many-body systemsParticipant, 11/09/2017 - 15/09/2017Venue: Arnold Sommerfeld Center for Theoretical Physics, LMU, Munich, GermanyLecturers (and preliminary topics):Philippe Corboz (Amsterdam): Projected entangled pair states (PEPS) (introduction)Olivier Parcollet (Saclay): Dynamical Mean Field Theory (DMFT) and impurity solversLode Pollet (LMU): Quantum Monte Carlo methodsUlrich Schollwoeck (LMU): Matrix product states (MPS), Density matrix renormalization group (DMRG)Norbert Schuch (MPQ): PEPS (mathematical aspects)Andreas Weichselbaum (LMU): Numerical renormalization group (NRG)Steve White (UC Irvine): DMRG in two dimensionsWebsite International Conference on Strongly Correlated Electron Systems 2017 (SCES2017)Participant, 16/07/2017 - 21/07/2017Venue: Clarion Congress Hotel Prague, Prague, Czech RepublicPoster: Charge-density-wave phases of a one-dimensional model with long-range repulsive interactionsWebsite The 35th International Symposium on Lattice Field Theory (Lattice 2017)Participant, 18/06/2017 - 24/06/2017Venue: Palacio de Congresos de Granada, Granada, SpainPoster: Charge-density-wave phases of a one-dimensional model with long-range repulsive interactionsAbstract:The one-dimensional extended t-V model on a lattice describes fermions with repulsive interactions of finite range and exhibits a quantum phase transition between a Luttinger liquid conducting phase and a Mott insulating phase. Its properties make it useful in the description of candidate materials for Mott transistor devices. It is known that by tailoring the potential energy of the insulating system, one can force a phase transition into a different insulating phase [1, 2]. We show how to construct all possible charge-density-wave phases of the system at low critical densities in the atomic limit. Higher critical densities are investigated by a brute-force analysis of the possible finite unit cells of the Fock states. We present example phase diagrams of the system.We construct a matrix product operator representation of the Hamiltonian of the t-V model. Using the matrix product states (MPS) approach we go beyond the atomic limit, where the phase diagrams are much richer. MPS method is especially problematic near the transition between two different charge-density-wave phases and we show how the bond dimension must be increased in order to converge the results.Our results indicate that the number of possible insulating phases grows with both the maximum interaction range and the fermion density and may cause the loss of insulating properties of the material at finite temperatures.References:[1] P. Schmitteckert and R. Werner, Phys. Rev. B, 69, 195115 (2004).[2] T. Mishra, J. Carrasquilla, and M. Rigol, Phys. Rev. B, 84, 115135 (2011).Website N8 HPC Network Event - New approaches to atomistic / quantum simulation of materialsSpeaker, 07/01/2017Venue: The Bar Convent, York, UKTalk: Effects of strain in graphene/hexagonal-boron-nitride heterostructuresM. Szyniszewski, E. Mostaani, N.D. Drummond, V.I. Fal'koWebsite The 34th International Symposium on Lattice Field Theory (Lattice 2016)Participant, 24/07/2016 - 30/07/2016Venue: University of Southampton, Southampton, UKPoster: Fermions with long-range interactions using a matrix-product-states approachAbstract:The long-range t-V model of fermions on a lattice is known to exhibit a transition between a Luttinger liquid phase and a Mott insulator phase [1]. At insulating densities, one can tailor the potential energy of the model in such a way that one forces a quantum phase transition to either another insulating charge-density-wave phase, a bond-order phase or a Luttinger liquid [2]. We show how to construct a matrix product operator representation of the Hamiltonian of the t-V model and we present phase diagrams calculated using the matrix-product-states approach [3]. We compare these phase diagrams with results obtained in the atomic limit.References:[1] G. Gomez-Santos, Phys. Rev. Lett. 70, 3780 (1993).[2] P. Schmitteckert and R. Werner, Phys. Rev. B 69, 195115 (2004); T. Mishra et al., Phys. Rev. B 84, 115135 (2011).[3] D. Perez-Garcia et al., Quantum Inf. Comput. 7, 401 (2007); F. Verstraete et al., Adv. Phys. 57, 143 (2008).Website NoWNano Summer Conference 2016Speaker, 27/06/2016 - 30/06/2016Venue: Cranage Hall, Cheshire, UKTalk: Diffusion Monte Carlo study of charge carrier complexes in two-dimensional semiconductorsM. Szyniszewski, E. Mostaani, C. Price, R. Maezono, N. Drummond, V. Fal'koWebsite CPP5 and N8 HPC Network Event - New approaches to atomistic / quantum simulation of materialsSpeaker, 08/01/2016Venue: The Bar Convent, York, UKTalk: Diffusion Monte Carlo study of charge carrier complexes in two-dimensional semiconductorsM. Szyniszewski, E. Mostaani, C. Price, R. Maezono, N. Drummond, V. Fal'koWebsite Psi-k 2015 ConferenceSpeaker, 06/09/2015 - 11/09/2015Venue: Kursaal Event Centre, San Sebastian / Donostia, SpainTalk: Diffusion Monte Carlo study of charge carrier complexes in two-dimensional semiconductorsM. Szyniszewski, E. Mostaani, N. Drummond, V. Fal'koAbstract:We use a novel description of the interaction between charges in two-dimensional (2D) semiconductors to investigate the binding properties of two-, three- and four-particle complexes of charge carriers (excitons, trions and biexcitons). We report binding energies and pair distribution functions calculated using diffusion quantum Monte Carlo methods, which are exact for these systems. Our results will enable the interpretation of experimental photoabsorption and photoluminescence measurements on 2D transition-metal dichalcogenide materials. We show that our data are consistent with previous binding-energy data for the limits in which the interactions between charges reduce to logarithmic and Coulomb (1/r) forms. We find that the logarithmic interaction that has previously been used to study excitons and trions in 2D semiconductors provides an inadequate description of the behaviour of systems such as molybdenum disulphide, and we provide accurate binding-energy data for excitons, trions and biexcitons in these materials.Website The 33rd International Symposium on Lattice Field Theory (Lattice 2015)Participant, 13/07/2015 - 18/07/2015Venue: Kobe International Conference Center, Kobe, JapanPoster: Strong coupling expansion of the $t$-$V$ model (further results)M. Szyniszewski, E. BurovskiAbstract:We employ a strong coupling expansion - similar to the one used in the lattice field theory studies [1] - to solve the one-dimensional extended $t$-$V$ model of fermions on a lattice [2]. This model is solved for a range of filling factors, including both commensurate - where a charge density wave is present - and incommensurate densities. The first set consists not only of a trivial case of half filling. The method allows us to trace the transition from a Luttinger liquid phase to a Mott insulating phase and calculate the critical parameter $K$. This simple yet powerful method is not based on Bethe ansatz and it works for both integrable and non-integrable systems. Furthermore, we investigate how tailoring the interaction can introduce other ordered phases of the system [3].References:[1] C.J. Hamer, Phys. Lett. B 82, 75-78 (1979); D.P. Crewther, C.J. Hamer, Nucl. Phys. B 170, 353-368 (1980).[2] G. Gomez-Santos, Phys. Rev. Lett. 70, 3780 (1993); R.G. Dias, Phys. Rev. B 62, 7791 (2000).[3] P. Schmitteckert, R. Werner, Phys. Rev. B 69, 195115 (2004); T. Mishra et al., Phys. Rev. B 84, 115135 (2011).Website Tensor Network Summer School 2015Participant, 01/06/2015 - 05/06/2015Venue: Ghent University, Ghent, BelgiumTopics:matrix product states (MPS)projected entangled pair states (PEPS)multiscale entanglement renormalization ansatz (MERA)Website International Conference on Strongly Correlated Electron Systems 2014Participant, 07/07/2014 - 11/07/2014Venue: Campus Saint Martin d'Heres, Grenoble, FrancePoster: Generalised $t$-$V$ model in one dimensionM. Szyniszewski, E. BurovskiAbstract:We use a strong coupling expansion [1] to solve the one-dimensional extended $t$-$V$ model of fermions [2,3]. The model is solved for a range of densities, including both commensurate - where a charge density wave is present - and incommensurate densities. The first set consists not only of a trivial case of half filling. The method allows us to trace the transition from a Luttinger liquid phase to a Mott insulating phase. This simple yet powerful method is not based on Bethe ansatz and it works for both integrable and non-integrable systems.References:[1] C.J. Hamer, Phys. Lett. B 82, 75-78 (1979).[2] G. Gomez-Santos, Phys. Rev. Lett. 70, 3780 (1993).[3] R.G. Dias, Phys. Rev. B 62, 7791 (2000).Website The 32nd International Symposium on Lattice Field Theory (Lattice 2014)Speaker, 22/06/2014 - 28/06/2014Venue: Columbia University, New York, USTalk: Lattice Hamiltonian approach to the Schwinger modelK. Cichy, A. Kujawa-Cichy, M. SzyniszewskiAbstract:We employ exact diagonalization with strong coupling expansion to the massless and massive Schwinger model. For the massless case, this allows us for a high accuracy continuum limit estimation of the ground state energy and scalar and vector mass gaps with precisions of the order of one part per billion or better. Furthermore, we investigate the chiral condensate and compare our calculations to previous results available in the literature. Oscillations of the chiral condensate which are present while increasing the expansion order are also studied and are shown to be directly linked to the presence of flux loops in the system.Website NoWNano Summer Conference 2014Participant, 09/06/2014 - 11/06/2014Venue: Cranage Hall, Cheshire, UKWebsite NoWNano Summer Conference 2013Participant, 17/06/2013 - 20/06/2013Venue: Cranage Hall, Cheshire, UKWebsite

The 34th International Symposium on Lattice Field Theory (Lattice 2016)
Participant, 24/07/2016 – 30/07/2016
Venue: University of Southampton, Southampton, UK

Poster: Fermions with long-range interactions using a matrix-product-states approach
M. Szyniszewski

Abstract:
​The long-range t-V model of fermions on a lattice is known to exhibit a transition between a Luttinger liquid phase and a Mott insulator phase [1]. At insulating densities, one can tailor the potential energy of the model in such a way that one forces a quantum phase transition to either another insulating charge-density-wave phase, a bond-order phase or a Luttinger liquid [2]. We show how to construct a matrix product operator representation of the Hamiltonian of the t-V model and we present phase diagrams calculated using the matrix-product-states approach [3]. We compare these phase diagrams with results obtained in the atomic limit.

NoWNano Summer Conference 2016
Speaker, 27/06/2016 – 30/06/2016​
Venue: Cranage Hall, Cheshire, UK

Talk: Diffusion Monte Carlo study of charge carrier complexes in two-dimensional semiconductors
M. Szyniszewski, E. Mostaani, C. Price, R. Maezono, N. Drummond, V. Fal’ko

N8 HPC Network Event – New approaches to atomistic / quantum simulation of materials
Speaker, 08/01/2016
Venue: The Bar Convent, York, UK

Talk: Diffusion Monte Carlo study of charge carrier complexes in two-dimensional semiconductors
M. Szyniszewski, E. Mostaani, C. Price, R. Maezono, N. Drummond, V. Fal’ko

Psi-k 2015 Conference
Speaker, 06/09/2015 – 11/09/2015
Venue: Kursaal Event Centre, San Sebastian / Donostia, Spain

Talk: Diffusion Monte Carlo study of charge carrier complexes in two-dimensional semiconductors
M. Szyniszewski, E. Mostaani, N. Drummond, V. Fal’ko

Abstract:
We use a novel description of the interaction between charges in two-dimensional (2D) semiconductors to investigate the binding properties of two-, three- and four-particle complexes of charge carriers (excitons, trions and biexcitons). We report binding energies and pair distribution functions calculated using diffusion quantum Monte Carlo methods, which are exact for these systems. Our results will enable the interpretation of experimental photoabsorption and photoluminescence measurements on 2D transition-metal dichalcogenide materials. We show that our data are consistent with previous binding-energy data for the limits in which the interactions between charges reduce to logarithmic and Coulomb (1/r) forms. We find that the logarithmic interaction that has previously been used to study excitons and trions in 2D semiconductors provides an inadequate description of the behaviour of systems such as molybdenum disulphide, and we provide accurate binding-energy data for excitons, trions and biexcitons in these materials.

Grant: IOP Research Student Conference Fund awarded by IOP Computational Physics Group; Psi-k Conference Financial Support.PRESENTATION

The 33rd International Symposium on Lattice Field Theory (Lattice 2015)
Participant, 13/07/2015 – 18/07/2015
Venue: Kobe International Conference Center, Kobe, Japan

Poster: Strong coupling expansion of the t-V model (further results)
M. Szyniszewski, E. Burovski

Abstract:
We employ a strong coupling expansion – similar to the one used in the lattice field theory studies [1] – to solve the one-dimensional extended t-V model of fermions on a lattice [2]. This model is solved for a range of filling factors, including both commensurate – where a charge density wave is present – and incommensurate densities. The first set consists not only of a trivial case of half filling. The method allows us to trace the transition from a Luttinger liquid phase to a Mott insulating phase and calculate the critical parameter K. This simple yet powerful method is not based on Bethe ansatz and it works for both integrable and non-integrable systems. Furthermore, we investigate how tailoring the interaction can introduce other ordered phases of the system [3].

Tensor Network Summer School 2015
Participant, 01/06/2015 – 05/06/2015
Venue: Ghent University, Ghent, Belgium

Topics:
– matrix product states (MPS)
– projected entangled pair states (PEPS)
– multiscale entanglement renormalization ansatz (MERA)

Travel grant: Lancaster University Graduate School Travel Grant GSTG-15-76.

International Conference on Strongly Correlated Electron Systems 2014
Participant, 07/07/2014 – 11/07/2014
Venue: Campus Saint Martin d’Hères, Grenoble, France

Poster: Generalised t-V model in one dimension
M. Szyniszewski, E. Burovski

Abstract:
We use a strong coupling expansion [1] to solve the one-dimensional extended t‑V model of fermions [2,3]. The model is solved for a range of densities, including both commensurate – where a charge density wave is present – and incommensurate densities. The first set consists not only of a trivial case of half filling. The method allows us to trace the transition from a Luttinger liquid phase to a Mott insulating phase. This simple yet powerful method is not based on Bethe ansatz and it works for both integrable and non-integrable systems.

Travel grant: Lancaster University Graduate School Travel Grant GSTG-14-26.

The 32nd International Symposium on Lattice Field Theory (Lattice 2014)
Speaker, 22/06/2014 – 28/06/2014
Venue: Columbia University, New York, US

Talk: Lattice Hamiltonian approach to the Schwinger model
K. Cichy, A. Kujawa-Cichy, M. Szyniszewski

Abstract:
We employ exact diagonalization with strong coupling expansion to the massless and massive Schwinger model. For the massless case, this allows us for a high accuracy continuum limit estimation of the ground state energy and scalar and vector mass gaps with precisions of the order of one part per billion or better. Furthermore, we investigate the chiral condensate and compare our calculations to previous results available in the literature. Oscillations of the chiral condensate which are present while increasing the expansion order are also studied and are shown to be directly linked to the presence of flux loops in the system.
PRESENTATION

## Outreach Events

 British Science WeekOrganiser, 18/03/2015Sackville Street Building, University of ManchesterActivities:making graphene and playing with models of carbon materialscrystallography: how a shadow of a 3D shape can change depending on the angle Science SpectacularOrganiser, 25/10/2014Whitworth Hall / Museum, University of ManchesterActivities:making graphenecrystallography: making shapes and looking at their shadows National Science and Engineering WeekOrganiser, 21/03/2014Sackville Street Building, University of ManchesterActivities:hydrophobic sandmaking graphene Meet the NanoscientistOrganiser, 09/02/2013Museum of Science and Industry, ManchesterActivities:hydrophobic sand and coatLEGO magnetic force microscopemaking grapheneferrofluids