Breakthrough in the description of warm dense matter
A team from the Institute of Theoretical Physics and Astrophysics at Kiel University, headed by Professor Michael Bonitz, has now been able to discover new findings on so-called warm dense matter. Physicists use this term to describe a state of matter that differs completely from those solid, liquid or gas states or plasmas known on earth.
Warm dense matter displays characteristics of all other physical states at the same time, in apparent contradiction. The Kiel-based scientists have now developed a new simulation technique which overcomes the inaccuracies of existing theoretical models in describing this state of matter. They have published their research findings in the current edition of the journal Physical Review Letters.
With a density of up to a thousand times more than normal solids, warm dense matter is extremely dense. It exists, for example, as a consequence of the enormous gravitation inside dwarf stars. In lab experiments, this state can be created for short periods of time, in the nano- to microsecond range, under the influence of high intensity laser radiation. Long enough for researchers across the world to probe this state of matter with experiments or computer simulations.
"Exact knowledge about warm dense matter is the key to answering many astrophysical questions. For example, it helps us to determine how old galaxies are, and is also essential for technological applications such as inertial confinement fusion or for understanding how materials behave under extreme pressure", says Bonitz, to classify the significance of the findings.
Previous theoretical models were only able to produce approximate information on the characteristics of warm dense matter. The reason for this is the particular complexity of the interaction between the constituent particles, but especially the behaviour of the electrons involved. They strongly interact with each other and, at the same time, are governed by the laws of quantum mechanics, so that until now they could not be described reliably using existing models.
Thanks to the new simulation method it is now possible to better understand the results of experiments and to make reliable predictions for new measurements. The Kiel-based research group's approach avoids the simplifications used in previous theoretical models.
"It is therefore justified to regard our approach as a computer experiment that produces exact results", Bonitz continues. These findings made at Kiel University now form the basis for improving the existing and developing new numerical methods that will allow for a complete description of warm dense matter in the future.
Schoof, T., Groth, S., Vorberger, J. and M. Bonitz (2015): Ab Initio Thermodynamic Results for the Degenerate Electron Gas at Finite Temperature, Physical Review Letters 115.
Prof. Michael Bonitz
Institut für Theoretische Physik und Astrophysik,
Tel.: +49 (0)431/-880-4122
The Bonitz Group, Institute of Theoretical Physics and Astrophysics:
Details, only a millionth fraction of a millimetre small: This is what Kiel University's research focus "Kiel Nano, Surface and Interface Science" (KiNSIS) is busy investigating. In the nano cosmos, other than in our macroscopic world, the rules of quantum physics apply. In KiNSIS, material scientists, chemists, physicists, biologists, electrical engineers, information scientists, food scientists and physicians work closely together. They aim at understanding systems in the nano dimension and turning knowledge into applications. Molecular machines, novel sensors, bionic materials, quantum computers, advanced therapies and much more can emerge from this endeavour.
More information at www.kinsis.uni-kiel.de/en
Christian-Albrechts-Universität zu Kiel
Press, Communication and Marketing, Dr Boris Pawlowski, Text/editing: Christian Urban
Postal address: D-24098 Kiel, Germany, Telephone: +49 (0)431 880-2104, Fax: +49 (0)431 880-1355
E-mail: firstname.lastname@example.org, Internet: www.uni-kiel.de, Jubilee: www.uni-kiel.de/cau350
Twitter: www.twitter.com/kieluni , Facebook: www.facebook.com/kieluni
Dr. Boris Pawlowski | Christian-Albrechts-Universität zu Kiel
From rocks in Colorado, evidence of a 'chaotic solar system'
23.02.2017 | University of Wisconsin-Madison
Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
24.02.2017 | Earth Sciences
24.02.2017 | Agricultural and Forestry Science
24.02.2017 | Life Sciences