• Direct imaging of orbitals in quantum materials7彩彩票app下载安装

    2019Tjeng, Liu Hao
    The search for new quantum materials with novel properties is often focused on materials containing transition-metal or rare-earth elements. The presence of the atomic-like d or f orbitals provides a fruitful playground to generate novel phenomena. In order to efficiently design and tune the materials, it is essential to identify the d or f orbitals that actively participate in the formation of the ground state. Here we developed a new experimental method that circumvents the need for theory and instead provides the information as measured.


  • Evidence for Weyl fermions by the local nuclear magnetic resonance techniques7彩彩票app下载安装

    2018Baenitz, Michael
    Tantalum has one of the largest quadrupole moments among all elements which makes it a rather useful local probe for excitations of Weyl fermions in the new Weyl semimetal TaP. We found three NQR lines in a good agreement with theoretical calculations including spin orbit coupling. The temperature dependence of the spin lattice relaxation rate is attributed to the magnetic excitations at the Weyl nodes and a good agreement with predictions from theory could be found. The microscopic magnetic resonance techniques therefore provide new insides into the class of Weyl semimetals.


  • The quantum sound of metals7彩彩票app下载安装

    2017Hassinger, Elena
    Every musical instrument has its own sound with a frequency spectrum that is determined by the shape of the instrument. In analogy to that, every metal has its characteristic frequency spectrum reflecting the properties of its electrons. Our investigation of the quantum sound of electrons in the metal PdRhO2 shows that electrons move quickly in the crystallographic planes whereas they hardly move perpendicular to the planes. The quantum music sounds slightly differently than expected and will help understand the particular hydrodynamic transport properties of electrons in these metals.


  • Covalence and ionicity in compounds of MgAgAs-type: from concepts to structure prediction7彩彩票app下载安装

    2016Wagner, Frank R.; Bende, David; Grin, Yuri
    Analysis of chemical bonding in compounds of the MgAgAs type of structure by bonding indicators in position space resulted in a generalization of the 8­–N rule for bonds of variable polarity. Position-space indicators enable quantification of ionicity and covalence, which was successfully used to explain the different site preference in main-group and transition-metal compounds of the MgAgAs type. On this basis, it was possible to propose promising candidates for new compounds with the MgAgAs structure type, which was subsequently verified for the majority of compounds by laboratory synthesis.


  • Topological Weyl semimetals7彩彩票app下载安装

    2015Yan, Binghai; Felser, Claudia
    In recent years, theoretical physicists discovered that the topology of a material can lead to interesting new quantum properties. This simple concept can be applied to the electronic structure of semiconducting materials in which relativistic effects are important. In 2015, several materials like NbP, NbAs, TaP, TaAs, und MoTe2 have been suggested by theoreticians as promissing, so-called Weyl semimetals, and have been physically characterized just a bit later. The special feature is that Weyl fermions, which occur in these materials as quasiparticles, exist in two chiralities.


  • Hunting for the electrical properties of topological insulators7彩彩票app下载安装

    2014Höfer, Katharina; Becker, Christoph; Rata, Diana; Swanson, Jesse; Thalmeier, Peter; Tjeng, Liu Hao
    Topological insulators form a novel state of matter that open up new opportunities to create unique quantum particles. Many exciting experiments have been proposed by theory, but still await their experimental verification, not to mention their implementation into applications. The main obstacle is the extrinsic conductivity associated with the unavoidable presence of defects in their bulk, as well as impurities on their surfaces. For Bi2Te3 films it is possible to obtain the desired quality by carrying out the preparation and characterization entirely under ultra-high vacuum conditions.


  • There's life in the old dog yet: discovery of a supercool magnet7彩彩票app下载安装

    2013Brando, Manuel; Steppke, Alexander; Küchler, Robert; Lausberg, Stefan; Lengyel, Edit; Steinke, Lucia; Borth, Robert; Lühmann, Thomas; Krellner, Cornelius; Pedrero, Luis; Pfau, Heike; Tencé, Sophie; Rosner, Helge; Nicklas, Michael; Steglich, Frank; Geibel, Christoph

    767彩票下载送27元彩金  其次,金融不可自我循环、用泡沫麻痹自我继续聚焦全面提升产业基础和产业链水平的根本任务,坚持绿色发展和智能制造两大发展主题,着重解决控产能扩张、促产业集中、保资源安全行业三大痛点,持续推进国际化进程,努力推进相关工作,推动质量变革、效率变革、动力变革,实现更高质量、更有效率、更加公平、更可持续、更为安全的发展

  • From palladium to noble metal-free hydrogenation catalysts – intermetallic compounds in catalysis7彩彩票app下载安装

    2013Armbrüster, Marc; Kovnir, Kyrill; Friedrich, Matthias; Grin, Yuri

    729彩票app下载  背景:  青岛疫情溯源首次证实接触新冠病毒污染的外包装可导致感染  今年6月北京新发地疫情、7月大连疫情中,冷冻的进口海产品在其中扮演了重要角色展望未来,为了避免重蹈日韩经济危机的覆辙,中国金融供给侧改革要持续推进各类金融机构财务报表、资管产品透明度,特别是强化大企业集团和地方政府实际控制金融企业信息披露力度


  • Novel quantum states in metals7彩彩票app下载安装

    2012Kirchner, Stefan; Wirth, Steffen; Pfau, Heike; Friedemann, Sven; Stockert, Oliver; Geibel, Christoph; Si, Qimao; Steglich, Frank
    Quantum criticality is currently pursued across many areas of correlated matter. A particular focus is on quantum criticality in itinerant electron systems. It has been shown that the traditional theory of metals breaks down in the vicinity of a novel class of quantum critical points in metals. A better understanding of the physics of these novel quantum states yields new insights into the occurence of magnetism and superconductivity.
  • Topological insulators from a chemical point of view7彩彩票app下载安装

    2012Felser, Claudia; Chadov, Stanislav; Müchler, Lukas; Yan, Binghai; Kübler, Jürgen; Zhang, Shou-Cheng1

    767彩票app塔珀当时也是一脸崩溃  用30亿美元收购这家几个月前估值仅10亿美元的公司,苹果到底是为什么?  坊间流传的种种推测,就像库克在媒体发布会上夸赞Beats耳机是“由专家和挑剔的耳朵调制”一样,观众们的想法可能跟森海塞尔、三角铁、舒尔等也差不多,那就是——我信你个鬼


  • Sr3[Co(CN)3] and Ba3[Co(CN)3]: "Simple" compounds with extensive consequences on the chemistry of highly reduced metalates7彩彩票app下载安装

    2011Höhn, Peter; Jach, Franziska; Karabiyik, Boris; Agrestini, Stefano; Wagner, Frank-R.; Ruck, Michael; Tjeng, Liu Hao; Kniep, Rüdiger
    The CN ligands in the isotypic compounds Sr3[Co(CN)3] und Ba3[Co(CN)3] have lost their "innocence" by higher reduction and weakening of the C–N bond, for the first time. For cobalt a closed-shell (d10)-configuration was determined. The resulting mesomeric structures of the trigonal-planar complex anions, [Co1–(CN)2(CN)3–]6–,open new insight into the chemistry of metalates and coordination compounds of transition metals with CN ligands. Finally, consequences on the chemistry of carbonylmetalates can be expected, too.
  • Zero resistance by magnetism7彩彩票app下载安装

    2011Stockert, Oliver; Arndt, Julia; Jeevan, Hirale S.; Geibel, Christoph; Steglich, Frank
    The question about the origin of unconventional superconductivity is one of the central issues in current condensed matter physics. Within an international collaboration scientists from the Max Planck Institute for Chemical Physics of Solids discovered that magnetic interactions are responsible for the Cooper pair formation and hence for the lossless current transport. While in conventional superconductors magnetism is detrimental for superconductivity, magnetism is an essential prerequisite for superconductivity in materials displaying unconventional superconductivity.


  • From alchemy towards quantum dynamics: unravelling the secret of superducting, magnetism and structural instabilities in iron pnictides7彩彩票app下载安装

    2010Geibel, Christoph; Jesche, Anton; Kasinathan, Deepa; Krellner, Cornelius; Leithe-Jasper, Andreas; Nicklas, Michael; Rosner, Helge; Schnelle, Walter; Thalmeier, Peter; Borrmann, Horst; Caroca-Canales, Nubia; Kaneko, Koji; Kumar, Manoj; Miclea, Corneliu Florin; Ormeci, Alim; Schmidt, Burkhard; Schwarz, Ulrich
    The relationship between superconductivity, magnetism and structure in the recently discovered Iron-pnictide superconductors is presently one of the hot topics in solid state physics. These compounds are the subject of a broad research program at the Max Planck Institute for Chemical Physics of Solids, which includes crystal growth, measurements of a large variety of physical properties, up to theoretical calculations and modeling of the electronic properties. This collaborative research resulted in a significant progress in our understanding of the physics in those systems.


  • Hard-X ray photoelectron spectroscopy: New opportunities for chemical and physical analysis7彩彩票app下载安装

    2009Tjeng, Liu Hao; Weinen, Jonas
    The department "Physics of correlated Matters" of the Max Planck Institute for Chemical Physics of Solids in Dresden is installing a new spectrometer at the synchrotron research facility Spring8 in Japan to carry out photoemission measurements using hard x-rays. The high kinetic energies of the emitted photoelectrons provide a much increased probing depth, facilitating considerably the use of photoelectron spectroscopy for chemical analysis of a wide range of materials.


  • Magnetic resonance spectroscopy as a local probe: Investigations of structure and magnetism in intermetallic compounds7彩彩票app下载安装

    2008Haarmann, Frank; Baenitz, Michael; Brüning, Eva; Geibel, Christoph; Goebel, Thorsten; Jegli¿, Peter; Koch, Katrin; Pecher, Oliver; Rosner, Helge; Steglich, Frank; Grin, Yuri
    The interaction of structure and magnetism of intermetallic compounds depends on the local as well as on the periodic assembly of the atoms. In order to understand the contribution of the local properties investigations by means of appropriate methods are necessary. Nuclear magnetic resonance (NMR) spectroscopy seams to by highly suited for this task.


  • New phenomena in strongly correlated electron systems7彩彩票app下载安装

    2007Wirth, Steffen; Singh, Surjeet; Capan, Cigdem (Louisiana State University, Baton Rouge, USA); Nicklas, Michael; DiTusa, John F. (Louisiana State University, Baton Rouge, USA); Fisk, Zachary (University of California, Irvine, USA); Steglich, Frank
    Strong electronic correlations in solids may result in fascinating, yet often not fully understood phenomena. The latter include unconventional superconductivity and quantum criticality in heavy fermion metals. Here, magnetotransport measurements may shed light on the impact of antiferromagnetic spin fluctuations on these phenomena. Nonetheless, further detailed experimental and theoretical investigations are required for a more complete comprehension within this emerging field of solid state physics.


  • Cu(II)-Materials – Crystal chemistry meets Magnetism7彩彩票app下载安装

    2006Rosner, Helge; Schnelle, Walter; Schmitt, Miriam; Janson, Oleg (St. Petersburg State University, Russland); Gerlach, Sylvia; Schmidt, Marcus; Huang, Ya-Xi; Liu, Wei; Gippius, Andrei (Moscow State University, Russland); Johannes, Michelle Dawn (NRL Washington, USA); Drechsler, Stefan-Ludwig (IFW Dresden); Richter; Johannes (Universität Magdeburg); Kniep, Rüdiger
    Low-dimensional cuprate compounds show a variety of intriguing magnetic properties. We demonstrate that a combination of electronic structure and model calculations together with experimental results and crystal-chemical considerations can provide a deep understanding of this compound family on microscopic grounds.
  • Complexity in the world of intermetallic phases7彩彩票app下载安装

    2006Makongo, Julien Pierre Amelie; Burkhardt, Ulrich; Prots, Yurii; Niewa, Rainer; Kreiner, Guido
    Complex metallic alloy phases are intermetallic compounds with prominent features compared to simple metallic systems. They are based on giant unit cells comprising up to more than thousands atoms per cell, hierarchical structures and inherent disorder phenomena. The characteristic features originate from a cluster substructure, which controls short and long range order as well as the physical properties.


  • Filled Skutterudites – Physics and Chemistry of Iron-Antimonides of Alkali, Alkaline-Earth, and Rare-Earth Metals7彩彩票app下载安装

    2005Leithe-Jasper, Andreas; Schnelle, Walter; Rosner, Helge; Wirth, Steffen; Sichelschmidt, Jörg; Baenitz, Michael; Gippius, Andrei (Moscow State University, Moskau, Russland); Rabis, Annegrit; Raychaudhuri, Pratap (Tata Institute of Fundamental Research, Mumbai, Indien); Sheet, Goutam (Tata Institute of Fundamental Research, Mumbai, Indien); Burkhardt, Ulrich; Borrmann, Horst; Ramlau, Reiner; Mydosh, John A.; Steglich, Frank; Grin, Juri
    Novel ternary intermetallic compounds of iron and antimony with a crystal structure containing large cavities, which can be filled by an electropositive element, show unusual magnetic and thermal properties. A study of the chemical bonding and of the structure-properties relationship is presented.


  • ZrAs1,4Se0,5 – A non-magnetic Kondo system with properties of a normal metal7彩彩票app下载安装

    2004Niewa, Rainer; Schmidt, Marcus; Cichorek, Tomasz; Auffermann, Gudrun; Ramlau, Reiner; Prots, Yurii; Schmidt, Ulrike; Völzke, Anja; Schulze, Katja; Burkhardt, Ulrich; Borrmann, Horst; Cardoso-Gil, Raúl; Schnelle, Walter; Schlechte, Andreas; Steglich, Frank; Kniep, Rüdiger
    ThAsSe and UAsSe represent rare examples for non-magnetic Kondo systems. For deeper insight into this behaviour a compound with the same crystal structure type from the chemical system Zr–As–Se was studied extensively in terms of chemical composition, crystal structure and electrical resistivity at low temperatures. The results indicate the unusual behaviour of ZrAs1.4Se0.5 to be connected with dynamical phenomena within the anionic substructure.


  • Quantumphenomena and Superconductivity7彩彩票app下载安装

    2003Sparn, Günter; Gegenwart, Philipp; Sichelschmidt, Jörg; Coleman, Piers; Custers, Jeroen; Deppe, Micha; Ferstl, Julia; Geibel, Christoph; Grosche, Friedrich Malte; Neumaier, Karl; Pépin, Catherine; Steglich, Frank; Tokiwa, Yoshifumi; Trovarelli, Octavio; Voevodin, Vladimir; Wilhelm, Heribert; Yuan, Huiqiu
    All developments achieved to date in the fields of medical-, information- and sensor- technology are based on models which are well established in physics and chemistry and which reflect the state of knowledge of fundamental research until the middle of the last century. Further progress, however, seems to be possible only if we learn to understand a new state of condensed matter, which can not be described within the context of the established models. This new state is dominated by quantum phenomena. Quantum phenomena come into play, when spatial dimensions become smaller than the wavelength of light (nano-technology) or when extremely strong correlations build up among the electrons of the solid (Quantum Hall Effect, Collossal Magnetoresistance, High Temperature Superconductivity (HTSC)). Here we report two outstanding discoveries which could be particularly important for the understanding of the HTSC. At the heart of the description of HTSC lies the assumption that superconductivity is created by coupling the charge carriers via magnetic fluctuations. In CeCu2Si2, a compound whose properties are related to those of HTSC, we not only have found hints towards the existence of a magnetic coupling mechanism but furthermore, for the first time, have been able to collect evidence for the existence of an additional, completely new coupling mechanism. The second discovery concerns the physical properties of a strongly correlated electron system (YbRh2Si2) in the vicinity of the magnetic quantum critical point. In YbRh2Si2 the strongly interacting charge carriers can not be treated within the concept of weakly interacting heavy quasi particles, as it is successfully done in heavy electron metals away from quantum criticality. In contrast to hitherto models, the quasiparticles in YbRh2Si2 seem to disintegrate into a charge part (current) and a spin part (magnetism) when approaching the quantum critical point.
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