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Primeur weekly 2019-01-28

Focus

Prof. Dieter Kranzlmüller from the Leibniz Supercomputer Centre on German and European HPC: being best is better than being first ...

Quantum computing

Purdue dives deeper into potentially game-changing field of quantum science and engineering ...

Focus on Europe

New e-IRGSP6 support project held its kick-off meeting in Luxembourg ...

Powerful supercomputing to propel France's high-performance computing (HPC) and artificial intelligence (AI) research and development ...

PRACE to issue Call for Proposals for HPC compute resources from DECI-15 (Tier-1) ...

PRACE Summer of HPC 2019 has opened applications ...

New 2 Petaflop/s supercomputer at the University of Antwerp  ...

Dutch Government plans additional 100 million euro investment in science including 30 million for SKA Square Kilometre Array ...

Middleware

CMU's DeltaFS team aims to create smarter ways to organize and store supercomputer data ...

ScaleMP announces record results ...

Hardware

DDN's turnaround of Tintri wins Information Technology Deal of the Year Award ...

CSC, the Finnish IT Center for Science, and the Finnish Meteorological Institute select 200 Gigabit HDR InfiniBand to accelerate multi-phase supercomputer programme ...

2CRSI and "SNB Middle East" announce a distribution agreement ...

Aldec facilitates design prototyping in FPGA and prototype testing with new HES Proto-AXI ...

Applications

January kicks off a busy year of research as scientists gain access to the world's fastest supercomputer ...

National Center for Computational Sciences introduces HPC Core Operations Group ...

Network enhancement strengthens ties between OLCF and ESnet ...

Materials design centre receives $25 million grant ...

Birth of massive black holes in the early universe revealed ...

Transparent electronics research gains momentum ...

New insights into magnetic quantum effects in solids ...

Pilot line project lnPulse launches to give Europe edge in integrated photonics ...

New insights into magnetic quantum effects in solids


The model refers to a cubic crystal structure (pyrochlore lattice). Not only were magnetic interactions between the nearest neighbours included, but also with the next nearest neighbours (see drawing). Credit: HZB.
22 Jan 2019 Berlin - Atoms and molecules in crystalline solids are arranged in regular three-dimensional lattices. The atoms interact with each other via various forces, finally reaching a state of minimum energy. Near absolute zero, the lattice oscillations freeze, so that interactions between electron spins dominate. A particularly interesting case occurs when the spins cannot all align at the same time to reach a state of lowest energy. This results in a frustrated system in which the spins are almost completely disordered and are therefore referred to as a spin liquid.

One of the leading models for studying 3D frustrated quantum magnets is the Heisenberg model on a pyrochlore lattice - a simple cubic crystal structure. Nevertheless, it has so far been extremely difficult to derive practical predictions, i.e. for specific materials and temperatures, from this theoretical model.

Teams from Germany, Japan, Canada, and India have now jointly conducted systematic investigations of this model with the aid of a new theoretical method and solved several of these difficulties. It is possible with this new method to vary the spin value of the lattice atoms as well as the temperature and other interaction parameters, and to calculate the parameter ranges in which novel magnetic quantum effects occur. The calculations were carried out at the Leibniz Supercomputing Centre (LRZ) in Munich.

"We were able to show that quantum physical effects surprisingly only occur over very limited parameter ranges", explained theoretical physicist Prof. Johannes Reuther from the Helmholtz-Zentrum Berlin für Materialien und Energie (HZB), co-author of the study. These quantum effects are most pronounced at the smallest possible spin (spin value ½). However, spin systems in the crystal structure investigated by the teams already behave almost completely like classical physical systems at spin values of 1.5 and above.

The work published deepens our understanding of solids and contributes to the systematic advancement of the search for 3D spin fluids in quantum materials.

The study is published Open Access inPhysical Review X(2019) and is titled " Quantum and Classical Phases of the Pyrochlore Heisenberg Model with Competing Interactions ". Yasir Iqbal, Tobias Müller, Pratyay Ghosh, Michel J. P. Gingras, Harald O. Jeschke, Stephan Rachel, Johannes Reuther, and Ronny Thomale are the authors.
Source: Helmholtz-Zentrum Berlin für Materialien und Energie

Back to Table of contents

Primeur weekly 2019-01-28

Focus

Prof. Dieter Kranzlmüller from the Leibniz Supercomputer Centre on German and European HPC: being best is better than being first ...

Quantum computing

Purdue dives deeper into potentially game-changing field of quantum science and engineering ...

Focus on Europe

New e-IRGSP6 support project held its kick-off meeting in Luxembourg ...

Powerful supercomputing to propel France's high-performance computing (HPC) and artificial intelligence (AI) research and development ...

PRACE to issue Call for Proposals for HPC compute resources from DECI-15 (Tier-1) ...

PRACE Summer of HPC 2019 has opened applications ...

New 2 Petaflop/s supercomputer at the University of Antwerp  ...

Dutch Government plans additional 100 million euro investment in science including 30 million for SKA Square Kilometre Array ...

Middleware

CMU's DeltaFS team aims to create smarter ways to organize and store supercomputer data ...

ScaleMP announces record results ...

Hardware

DDN's turnaround of Tintri wins Information Technology Deal of the Year Award ...

CSC, the Finnish IT Center for Science, and the Finnish Meteorological Institute select 200 Gigabit HDR InfiniBand to accelerate multi-phase supercomputer programme ...

2CRSI and "SNB Middle East" announce a distribution agreement ...

Aldec facilitates design prototyping in FPGA and prototype testing with new HES Proto-AXI ...

Applications

January kicks off a busy year of research as scientists gain access to the world's fastest supercomputer ...

National Center for Computational Sciences introduces HPC Core Operations Group ...

Network enhancement strengthens ties between OLCF and ESnet ...

Materials design centre receives $25 million grant ...

Birth of massive black holes in the early universe revealed ...

Transparent electronics research gains momentum ...

New insights into magnetic quantum effects in solids ...

Pilot line project lnPulse launches to give Europe edge in integrated photonics ...