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Wagner N, Crippa L, Amaricci A, Hansmann P, Klett M, König EJ, Schäfer T, Sante DD, Cano J, Millis AJ, Georges A, Sangiovanni G. Mott insulators with boundary zeros. Nat Commun 2023; 14:7531. [PMID: 37985660 PMCID: PMC10662449 DOI: 10.1038/s41467-023-42773-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 10/17/2023] [Indexed: 11/22/2023] Open
Abstract
The topological classification of electronic band structures is based on symmetry properties of Bloch eigenstates of single-particle Hamiltonians. In parallel, topological field theory has opened the doors to the formulation and characterization of non-trivial phases of matter driven by strong electron-electron interaction. Even though important examples of topological Mott insulators have been constructed, the relevance of the underlying non-interacting band topology to the physics of the Mott phase has remained unexplored. Here, we show that the momentum structure of the Green's function zeros defining the "Luttinger surface" provides a topological characterization of the Mott phase related, in the simplest description, to the one of the single-particle electronic dispersion. Considerations on the zeros lead to the prediction of new phenomena: a topological Mott insulator with an inverted gap for the bulk zeros must possess gapless zeros at the boundary, which behave as a form of "topological antimatter" annihilating conventional edge states. Placing band and Mott topological insulators in contact produces distinctive observable signatures at the interface, revealing the otherwise spectroscopically elusive Green's function zeros.
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Affiliation(s)
- N Wagner
- Institut für Theoretische Physik und Astrophysik, Universität Würzburg, 97074, Würzburg, Germany
| | - L Crippa
- Institut für Theoretische Physik und Astrophysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Universität Würzburg, 97074, Würzburg, Germany
| | - A Amaricci
- CNR-IOM, Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche, Via Bonomea 265, 34136, Trieste, Italy
| | - P Hansmann
- Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - M Klett
- Max-Planck-Institut für Festkörperforschung, Heisenbergstr. 1, 70569, Stuttgart, Germany
| | - E J König
- Max-Planck-Institut für Festkörperforschung, Heisenbergstr. 1, 70569, Stuttgart, Germany
| | - T Schäfer
- Max-Planck-Institut für Festkörperforschung, Heisenbergstr. 1, 70569, Stuttgart, Germany
| | - D Di Sante
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy
- Center for Computational Quantum Physics, Flatiron Institute, New York, NY, USA
| | - J Cano
- Center for Computational Quantum Physics, Flatiron Institute, New York, NY, USA
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York, NY, 11974, USA
| | - A J Millis
- Center for Computational Quantum Physics, Flatiron Institute, New York, NY, USA
- Department of Physics, Columbia University, New York, NY, USA
| | - A Georges
- Center for Computational Quantum Physics, Flatiron Institute, New York, NY, USA
- Collège de France, PSL University, 11 place Marcelin Berthelot, 75005, Paris, France
- Department of Quantum Matter Physics, University of Geneva, 24 quai Ernest-Ansermet, 1211, Geneva, Switzerland
- CPHT, CNRS, École Polytechnique, IP Paris, F-91128, Palaiseau, France
| | - G Sangiovanni
- Institut für Theoretische Physik und Astrophysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Universität Würzburg, 97074, Würzburg, Germany.
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2
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Suzuki H, Wang L, Bertinshaw J, Strand HUR, Käser S, Krautloher M, Yang Z, Wentzell N, Parcollet O, Jerzembeck F, Kikugawa N, Mackenzie AP, Georges A, Hansmann P, Gretarsson H, Keimer B. Distinct spin and orbital dynamics in Sr 2RuO 4. Nat Commun 2023; 14:7042. [PMID: 37923750 PMCID: PMC10624926 DOI: 10.1038/s41467-023-42804-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 10/20/2023] [Indexed: 11/06/2023] Open
Abstract
The unconventional superconductor Sr2RuO4 has long served as a benchmark for theories of correlated-electron materials. The determination of the superconducting pairing mechanism requires detailed experimental information on collective bosonic excitations as potential mediators of Cooper pairing. We have used Ru L3-edge resonant inelastic x-ray scattering to obtain comprehensive maps of the electronic excitations of Sr2RuO4 over the entire Brillouin zone. We observe multiple branches of dispersive spin and orbital excitations associated with distinctly different energy scales. The spin and orbital dynamical response functions calculated within the dynamical mean-field theory are in excellent agreement with the experimental data. Our results highlight the Hund metal nature of Sr2RuO4 and provide key information for the understanding of its unconventional superconductivity.
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Affiliation(s)
- H Suzuki
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany.
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, 980-8578, Japan.
- Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, Sendai, 980-8578, Japan.
| | - L Wang
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
| | - J Bertinshaw
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
| | - H U R Strand
- School of Science and Technology, Örebro University, Fakultetsgatan 1, SE-701 82, Örebro, Sweden
- Institute for Molecules and Materials, Radboud University, 6525 AJ, Nijmegen, the Netherlands
| | - S Käser
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
- Department of Physics, Friedrich-Alexander-University (FAU) of Erlangen-Nürnberg, 91058, Erlangen, Germany
| | - M Krautloher
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
| | - Z Yang
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
| | - N Wentzell
- Center for Computational Quantum Physics, Flatiron Institute, Simons Foundation, 162 5th Avenue, New York, 10010, USA
| | - O Parcollet
- Center for Computational Quantum Physics, Flatiron Institute, Simons Foundation, 162 5th Avenue, New York, 10010, USA
- Université Paris-Saclay, CNRS, CEA, Institut de physique théorique, 91191, Gif-sur-Yvette, France
| | - F Jerzembeck
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - N Kikugawa
- National Institute for Materials Science, Tsukuba, Ibaraki, 305-0003, Japan
| | - A P Mackenzie
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - A Georges
- Center for Computational Quantum Physics, Flatiron Institute, Simons Foundation, 162 5th Avenue, New York, 10010, USA
- Collége de France, 11 place Marcelin Berthelot, 75005, Paris, France
- Centre de Physique Théorique (CPHT), CNRS, Ecole Polytechnique, IP Paris, 91128, Palaiseau, France
- Department of Quantum Matter Physics, University of Geneva, 24 Quai Ernest-Ansermet, 1211, Geneva 4, Switzerland
| | - P Hansmann
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
- Department of Physics, Friedrich-Alexander-University (FAU) of Erlangen-Nürnberg, 91058, Erlangen, Germany
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - H Gretarsson
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany.
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, D-22607, Hamburg, Germany.
| | - B Keimer
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany.
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3
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Stierhof J, Kühn S, Winter M, Micke P, Steinbrügge R, Shah C, Hell N, Bissinger M, Hirsch M, Ballhausen R, Lang M, Gräfe C, Wipf S, Cumbee R, Betancourt-Martinez GL, Park S, Niskanen J, Chung M, Porter FS, Stöhlker T, Pfeifer T, Brown GV, Bernitt S, Hansmann P, Wilms J, Crespo López-Urrutia JR, Leutenegger MA. A new benchmark of soft X-ray transition energies of Ne , CO 2 , and SF 6 : paving a pathway towards ppm accuracy. Eur Phys J D At Mol Opt Phys 2022; 76:38. [PMID: 35273463 PMCID: PMC8888507 DOI: 10.1140/epjd/s10053-022-00355-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/23/2022] [Indexed: 06/14/2023]
Abstract
ABSTRACT A key requirement for the correct interpretation of high-resolution X-ray spectra is that transition energies are known with high accuracy and precision. We investigate the K-shell features of Ne , CO 2 , and SF 6 gases, by measuring their photo ion-yield spectra at the BESSY II synchrotron facility simultaneously with the 1s-np fluorescence emission of He-like ions produced in the Polar-X EBIT. Accurate ab initio calculations of transitions in these ions provide the basis of the calibration. While the CO 2 result agrees well with previous measurements, the SF 6 spectrum appears shifted by ∼ 0.5 eV, about twice the uncertainty of the earlier results. Our result for Ne shows a large departure from earlier results, but may suffer from larger systematic effects than our other measurements. The molecular spectra agree well with our results of time-dependent density functional theory. We find that the statistical uncertainty allows calibrations in the desired range of 1-10 meV, however, systematic contributions still limit the uncertainty to ∼ 40-100 meV, mainly due to the temporal stability of the monochromator energy scale. Combining our absolute calibration technique with a relative energy calibration technique such as photoelectron energy spectroscopy will be necessary to realize its full potential of achieving uncertainties as low as 1-10 meV.
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Affiliation(s)
- J. Stierhof
- Dr. Karl Remeis-Observatory and Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Sternwartstr. 7, 96049 Bamberg, Germany
| | - S. Kühn
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - M. Winter
- Institute of Theoretical Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 7/B2, 91058 Erlangen, Germany
- CNRS, Institut NEEL, Université Grenoble Alpes, CNRS, Institut NEEL, 25 rue des Martyrs BP 166, 38042 Grenoble Cedex 9, France
| | - P. Micke
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
- CERN, 1211 Geneva 23, Switzerland
| | - R. Steinbrügge
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - C. Shah
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd., Greenbelt, MD 20771 USA
- Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, CA 94550 USA
| | - N. Hell
- Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, CA 94550 USA
| | - M. Bissinger
- Dr. Karl Remeis-Observatory and Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Sternwartstr. 7, 96049 Bamberg, Germany
| | - M. Hirsch
- Dr. Karl Remeis-Observatory and Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Sternwartstr. 7, 96049 Bamberg, Germany
| | - R. Ballhausen
- Dr. Karl Remeis-Observatory and Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Sternwartstr. 7, 96049 Bamberg, Germany
| | - M. Lang
- Dr. Karl Remeis-Observatory and Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Sternwartstr. 7, 96049 Bamberg, Germany
| | - C. Gräfe
- Dr. Karl Remeis-Observatory and Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Sternwartstr. 7, 96049 Bamberg, Germany
| | - S. Wipf
- Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena, Germany
| | - R. Cumbee
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd., Greenbelt, MD 20771 USA
- Department of Astronomy, University of Maryland, College Park, MD 20742 USA
| | - G. L. Betancourt-Martinez
- Institut de Recherche en Astrophysique et Planétologie, 9, avenue du Colonel Roche BP 44346, 31028 Toulouse Cedex 4, France
| | - S. Park
- Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan, South Korea
| | - J. Niskanen
- Institute for Methods and Instrumentation in Synchrotron Radiation Research G-ISRR, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - M. Chung
- Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan, South Korea
| | - F. S. Porter
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd., Greenbelt, MD 20771 USA
| | - T. Stöhlker
- Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291 Darmstadt, Germany
- Helmholtz-Institut Jena, Fröbelstieg 3, 07743 Jena, Germany
| | - T. Pfeifer
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - G. V. Brown
- Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, CA 94550 USA
| | - S. Bernitt
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
- Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291 Darmstadt, Germany
- Helmholtz-Institut Jena, Fröbelstieg 3, 07743 Jena, Germany
| | - P. Hansmann
- Institute of Theoretical Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 7/B2, 91058 Erlangen, Germany
| | - J. Wilms
- Dr. Karl Remeis-Observatory and Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Sternwartstr. 7, 96049 Bamberg, Germany
| | | | - M. A. Leutenegger
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd., Greenbelt, MD 20771 USA
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4
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Guo H, Li ZW, Chang CF, Hu Z, Kuo CY, Perring TG, Schmidt W, Piovano A, Schmalzl K, Walker HC, Lin HJ, Chen CT, Blanco-Canosa S, Schlappa J, Schüßler-Langeheine C, Hansmann P, Khomskii DI, Tjeng LH, Komarek AC. Charge disproportionation and nano phase separation in [Formula: see text]. Sci Rep 2020; 10:18012. [PMID: 33093480 PMCID: PMC7582202 DOI: 10.1038/s41598-020-74884-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 09/04/2020] [Indexed: 11/29/2022] Open
Abstract
We have successfully grown centimeter-sized layered [Formula: see text] single crystals under high oxygen pressures of 120-150 bar by the floating zone technique. This enabled us to perform neutron scattering experiments where we observe close to quarter-integer magnetic peaks below [Formula: see text] that are accompanied by steep upwards dispersing spin excitations. Within the high-frequency Ni-O bond stretching phonon dispersion, a softening at the propagation vector for a checkerboard modulation can be observed. We were able to simulate the magnetic excitation spectra using a model that includes two essential ingredients, namely checkerboard charge disproportionation and nano phase separation. The results thus suggest that charge disproportionation is preferred instead of a Jahn-Teller distortion even for this layered [Formula: see text] system.
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Affiliation(s)
- H. Guo
- Max-Planck-Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
| | - Z. W. Li
- Max-Planck-Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
- Institute of Applied Magnetics, Key Lab for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou, 730000 People’s Republic of China
| | - C. F. Chang
- Max-Planck-Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
| | - Z. Hu
- Max-Planck-Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
| | - C.-Y. Kuo
- Max-Planck-Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
- National Synchrotron Radiation Research Center (NSRRC), 101 Hsin-Ann Road, Hsinchu, 30076 Taiwan
| | - T. G. Perring
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot, OX11 0QX UK
| | - W. Schmidt
- Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science at ILL, 71 avenue des Martyrs, 38000 Grenoble, France
| | - A. Piovano
- Institut Laue-Langevin, 71 avenue des Martyrs, 38000 Grenoble, France
| | - K. Schmalzl
- Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science at ILL, 71 avenue des Martyrs, 38000 Grenoble, France
| | - H. C. Walker
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot, OX11 0QX UK
| | - H. J. Lin
- National Synchrotron Radiation Research Center (NSRRC), 101 Hsin-Ann Road, Hsinchu, 30076 Taiwan
| | - C. T. Chen
- National Synchrotron Radiation Research Center (NSRRC), 101 Hsin-Ann Road, Hsinchu, 30076 Taiwan
| | - S. Blanco-Canosa
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Basque Country Spain
- Donostia International Physics Center, DIPC, 20018 Donostia-San Sebastian, Basque Country, Spain
| | - J. Schlappa
- European X-ray Free Electron Laser Facility GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
| | - C. Schüßler-Langeheine
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 15, 12489 Berlin, Germany
| | - P. Hansmann
- Max-Planck-Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
| | - D. I. Khomskii
- Physics Institute II, University of Cologne, Zülpicher Str. 77, 50937 Cologne, Germany
| | - L. H. Tjeng
- Max-Planck-Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
| | - A. C. Komarek
- Max-Planck-Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
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5
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Hansmann P, Brückner A, Kiontke S, Berkenfeld B, Seebohm G, Brouillard P, Vikkula M, Jansen FE, Nellist M, Oeckinghaus A, Kümmel D. Structure of the TSC2 GAP Domain: Mechanistic Insight into Catalysis and Pathogenic Mutations. Structure 2020; 28:933-942.e4. [PMID: 32502382 DOI: 10.1016/j.str.2020.05.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 02/06/2020] [Accepted: 05/15/2020] [Indexed: 12/17/2022]
Abstract
The TSC complex is the cognate GTPase-activating protein (GAP) for the small GTPase Rheb and a crucial regulator of the mechanistic target of rapamycin complex 1 (mTORC1). Mutations in the TSC1 and TSC2 subunits of the complex cause tuberous sclerosis complex (TSC). We present the crystal structure of the catalytic asparagine-thumb GAP domain of TSC2. A model of the TSC2-Rheb complex and molecular dynamics simulations suggest that TSC2 Asn1643 and Rheb Tyr35 are key active site residues, while Rheb Arg15 and Asp65, previously proposed as catalytic residues, contribute to the TSC2-Rheb interface and indirectly aid catalysis. The TSC2 GAP domain is further stabilized by interactions with other TSC2 domains. We characterize TSC2 variants that partially affect TSC2 functionality and are associated with atypical symptoms in patients, suggesting that mutations in TSC1 and TSC2 might predispose to neurological and vascular disorders without fulfilling the clinical criteria for TSC.
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Affiliation(s)
- Patrick Hansmann
- Westfälische Wilhelms-Universität, Institute of Biochemistry, Wilhelm Klemm-Str. 2, 48149 Münster, Germany
| | - Anne Brückner
- Westfälische Wilhelms-Universität, Institute of Biochemistry, Wilhelm Klemm-Str. 2, 48149 Münster, Germany; Westfälische Wilhelms-Universität, Institute of Molecular Tumor Biology, Robert-Koch-Str. 43, 48149 Münster, Germany
| | - Stephan Kiontke
- Philipps-Universität Marburg, Faculty of Biology, Department of Plant Physiology and Photobiology, Karl-von-Frisch-Str. 8, 35032 Marburg, Germany
| | - Bianca Berkenfeld
- Westfälische Wilhelms-Universität, Institute of Biochemistry, Wilhelm Klemm-Str. 2, 48149 Münster, Germany
| | - Guiscard Seebohm
- University Hospital Münster, Institute for Genetics of Heart Diseases, Department of Cardiovascular Medicine, Robert-Koch-Str. 45, 48149 Münster, Germany
| | - Pascal Brouillard
- Université Catholique de Louvain, de Duve Institute, Human Molecular Genetics, Brussels, Belgium
| | - Miikka Vikkula
- Université Catholique de Louvain, de Duve Institute, Human Molecular Genetics, Brussels, Belgium; WELBIO (Walloon Excellence in Lifesciences and Biotechnology), de Duve Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Floor E Jansen
- Department of Child Neurology, Brain Center UMC Utrecht, Utrecht, the Netherlands
| | - Mark Nellist
- Department of Clinical Genetics, Erasmus Medical Center, Wytemaweg 80, 3015 CN Rotterdam, the Netherlands
| | - Andrea Oeckinghaus
- Westfälische Wilhelms-Universität, Institute of Molecular Tumor Biology, Robert-Koch-Str. 43, 48149 Münster, Germany
| | - Daniel Kümmel
- Westfälische Wilhelms-Universität, Institute of Biochemistry, Wilhelm Klemm-Str. 2, 48149 Münster, Germany.
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6
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Bertinshaw J, Gurung N, Jorba P, Liu H, Schmid M, Mantadakis DT, Daghofer M, Krautloher M, Jain A, Ryu GH, Fabelo O, Hansmann P, Khaliullin G, Pfleiderer C, Keimer B, Kim BJ. Unique Crystal Structure of Ca_{2}RuO_{4} in the Current Stabilized Semimetallic State. Phys Rev Lett 2019; 123:137204. [PMID: 31697510 DOI: 10.1103/physrevlett.123.137204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 07/26/2019] [Indexed: 06/10/2023]
Abstract
The electric-current stabilized semimetallic state in the quasi-two-dimensional Mott insulator Ca_{2}RuO_{4} exhibits an exceptionally strong diamagnetism. Through a comprehensive study using neutron and x-ray diffraction, we show that this nonequilibrium phase assumes a crystal structure distinct from those of equilibrium metallic phases realized in the ruthenates by chemical doping, high pressure, and epitaxial strain, which in turn leads to a distinct electronic band structure. Dynamical mean field theory calculations based on the crystallographically refined atomic coordinates and realistic Coulomb repulsion parameters indicate a semimetallic state with partially gapped Fermi surface. Our neutron diffraction data show that the nonequilibrium behavior is homogeneous, with antiferromagnetic long-range order completely suppressed. These results provide a new basis for theoretical work on the origin of the unusual nonequilibrium diamagnetism in Ca_{2}RuO_{4}.
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Affiliation(s)
- J Bertinshaw
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - N Gurung
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - P Jorba
- Physik-Department, Technische Universität München, D-85748 Garching, Germany
| | - H Liu
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - M Schmid
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
- Institute for Functional Matter and Quantum Technologies, University of Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany
- Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany
| | - D T Mantadakis
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - M Daghofer
- Institute for Functional Matter and Quantum Technologies, University of Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany
- Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany
| | - M Krautloher
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - A Jain
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
- Solid State Physics Division, Bhabha Atomic Research Center, Mumbai 400 085, India
| | - G H Ryu
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - O Fabelo
- Institut Laue Langevin, BP 156, F-38042 Grenoble cedex 9, France
| | - P Hansmann
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzerstr Straße 40, D-01187 Dresden, Germany
| | - G Khaliullin
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - C Pfleiderer
- Physik-Department, Technische Universität München, D-85748 Garching, Germany
| | - B Keimer
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - B J Kim
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
- Department of Physics, Pohang University of Science and Technology, Pohang 790-784, South Korea
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), 77 Cheongam-Ro, Pohang 790-784, South Korea
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7
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Hansmann P, Ayral T, Tejeda A, Biermann S. Uncertainty principle for experimental measurements: Fast versus slow probes. Sci Rep 2016; 6:19728. [PMID: 26829902 PMCID: PMC4735290 DOI: 10.1038/srep19728] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 12/17/2015] [Indexed: 11/10/2022] Open
Abstract
The result of a physical measurement depends on the time scale of the experimental probe. In solid-state systems, this simple quantum mechanical principle has far-reaching consequences: the interplay of several degrees of freedom close to charge, spin or orbital instabilities combined with the disparity of the time scales associated to their fluctuations can lead to seemingly contradictory experimental findings. A particularly striking example is provided by systems of adatoms adsorbed on semiconductor surfaces where different experiments--angle-resolved photoemission, scanning tunneling microscopy and core-level spectroscopy--suggest different ordering phenomena. Using most recent first principles many-body techniques, we resolve this puzzle by invoking the time scales of fluctuations when approaching the different instabilities. These findings suggest a re-interpretation of ordering phenomena and their fluctuations in a wide class of solid-state systems ranging from organic materials to high-temperature superconducting cuprates.
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Affiliation(s)
- P Hansmann
- Centre de Physique Théorique, Ecole Polytechnique, CNRS, Univ. Paris-Saclay, 91128 Palaiseau, France.,Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany
| | - T Ayral
- Centre de Physique Théorique, Ecole Polytechnique, CNRS, Univ. Paris-Saclay, 91128 Palaiseau, France.,Institut de Physique Théorique (IPhT), CEA, CNRS, URA 2306, 91191 Gif-sur-Yvette, France
| | - A Tejeda
- Laboratoire de Physique des Solides, CNRS, Univ. Paris Sud, Univ. Paris-Saclay, 91405 Orsay, France
| | - S Biermann
- Centre de Physique Théorique, Ecole Polytechnique, CNRS, Univ. Paris-Saclay, 91128 Palaiseau, France.,Collège de France, 11 place Marcelin Berthelot, 75005 Paris, France.,European Theoretical Synchrotron Facility, Europe
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8
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Pourovskii LV, Hansmann P, Ferrero M, Georges A. Theoretical prediction and spectroscopic fingerprints of an orbital transition in CeCu2Si2. Phys Rev Lett 2014; 112:106407. [PMID: 24679316 DOI: 10.1103/physrevlett.112.106407] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Indexed: 06/03/2023]
Abstract
We show that the heavy-fermion compound CeCu2Si2 undergoes a transition between two regimes dominated by different crystal-field states. At low pressure P and low temperature T the Ce 4f electron resides in the atomic crystal-field ground state, while at high P or T, the electron occupancy and spectral weight is transferred to an excited crystal-field level that hybridizes more strongly with itinerant states. These findings result from first-principles dynamical-mean-field-theory calculations. We predict experimental signatures of this orbital transition in x-ray spectroscopy. The corresponding fluctuations may be responsible for the second high-pressure superconducting dome observed in this and similar materials.
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Affiliation(s)
- L V Pourovskii
- Centre de Physique Théorique, CNRS, École Polytechnique, 91128 Palaiseau, France and Swedish e-science Research Centre (SeRC), Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-58183 Linköping, Sweden
| | - P Hansmann
- Centre de Physique Théorique, CNRS, École Polytechnique, 91128 Palaiseau, France
| | - M Ferrero
- Centre de Physique Théorique, CNRS, École Polytechnique, 91128 Palaiseau, France
| | - A Georges
- Centre de Physique Théorique, CNRS, École Polytechnique, 91128 Palaiseau, France and Collège de France, 11 place Marcelin Berthelot, 75005 Paris, France and DPMC, Université de Genève, 24 quai Ernest Ansermet, CH-1211 Genève, Switzerland
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9
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Hansmann P, Ayral T, Vaugier L, Werner P, Biermann S. Long-range Coulomb interactions in surface systems: a first-principles description within self-consistently combined GW and dynamical mean-field theory. Phys Rev Lett 2013; 110:166401. [PMID: 23679625 DOI: 10.1103/physrevlett.110.166401] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Indexed: 06/02/2023]
Abstract
Systems of adatoms on semiconductor surfaces display competing ground states and exotic spectral properties typical of two-dimensional correlated electron materials which are dominated by a complex interplay of spin and charge degrees of freedom. We report a fully ab initio derivation of low-energy Hamiltonians for the adatom systems Si(111):X, with X=Sn, Si, C, Pb, that we solve within self-consistently combined GW and dynamical mean-field theory. Calculated photoemission spectra are in agreement with available experimental data. We rationalize experimentally observed trends from Mott physics toward charge ordering along the series as resulting from substantial long-range interactions.
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Affiliation(s)
- P Hansmann
- Centre de Physique Théorique, Ecole Polytechnique, CNRS UMR7644, 91128 Palaiseau, France
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10
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Lupi S, Baldassarre L, Mansart B, Perucchi A, Barinov A, Dudin P, Papalazarou E, Rodolakis F, Rueff JP, Itié JP, Ravy S, Nicoletti D, Postorino P, Hansmann P, Parragh N, Toschi A, Saha-Dasgupta T, Andersen OK, Sangiovanni G, Held K, Marsi M. Erratum: A microscopic view on the Mott transition in chromium-doped V2O3. Nat Commun 2012. [DOI: 10.1038/ncomms1397] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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11
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Uchida M, Ishizaka K, Hansmann P, Kaneko Y, Ishida Y, Yang X, Kumai R, Toschi A, Onose Y, Arita R, Held K, Andersen OK, Shin S, Tokura Y. Pseudogap of metallic layered nickelate R(2-x)Sr(x)NiO4 (R = Nd, Eu) crystals measured using angle-resolved photoemission spectroscopy. Phys Rev Lett 2011; 106:027001. [PMID: 21405246 DOI: 10.1103/physrevlett.106.027001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Revised: 11/20/2010] [Indexed: 05/30/2023]
Abstract
We have investigated charge dynamics and electronic structures for single crystals of metallic layered nickelates, R(2-x)Sr(x)NiO4 (R = Nd, Eu), isostructural to La(2-x)Sr(x)CuO4. Angle-resolved photoemission spectroscopy on the barely metallic Eu(0.9)Sr(1.1)NiO4 (R = Eu, x = 1.1) has revealed a large hole surface of x2-y2 character with a high-energy pseudogap of the same symmetry and comparable magnitude with those of underdoped (x<0.1) cuprates, although the antiferromagnetic interactions are 1 order of magnitude smaller. This finding strongly indicates that the momentum-dependent pseudogap feature in the layered nickelate arises from the real-space charge correlation.
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Affiliation(s)
- M Uchida
- Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan
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12
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Lupi S, Baldassarre L, Mansart B, Perucchi A, Barinov A, Dudin P, Papalazarou E, Rodolakis F, Rueff JP, Itié JP, Ravy S, Nicoletti D, Postorino P, Hansmann P, Parragh N, Toschi A, Saha-Dasgupta T, Andersen OK, Sangiovanni G, Held K, Marsi M. A microscopic view on the Mott transition in chromium-doped V2O3. Nat Commun 2010; 1:105. [DOI: 10.1038/ncomms1109] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Accepted: 10/07/2010] [Indexed: 11/09/2022] Open
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13
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Hansmann P, Arita R, Toschi A, Sakai S, Sangiovanni G, Held K. Dichotomy between large local and small ordered magnetic moments in iron-based superconductors. Phys Rev Lett 2010; 104:197002. [PMID: 20866992 DOI: 10.1103/physrevlett.104.197002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Indexed: 05/29/2023]
Abstract
We study a four-band model for iron-based superconductors within the local density approximation combined with dynamical mean-field theory (LDA+DMFT). This successfully reproduces the results of models which take As p degrees of freedom explicitly into account and has several physical advantages over the standard five d-band model. Our findings reveal that the new superconductors are more strongly correlated than their single-particle properties suggest. Two-particle correlation functions unveil the dichotomy between local and ordered magnetic moments in these systems, calling for further experiments to better resolve the short time scale spin dynamics.
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Affiliation(s)
- P Hansmann
- Institut for Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria
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14
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Rodolakis F, Hansmann P, Rueff JP, Toschi A, Haverkort MW, Sangiovanni G, Tanaka A, Saha-Dasgupta T, Andersen OK, Held K, Sikora M, Alliot I, Itié JP, Baudelet F, Wzietek P, Metcalf P, Marsi M. Inequivalent routes across the Mott transition in V2O3 explored by X-ray absorption. Phys Rev Lett 2010; 104:047401. [PMID: 20366736 DOI: 10.1103/physrevlett.104.047401] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Indexed: 05/29/2023]
Abstract
The changes in the electronic structure of V2O3 across the metal-insulator transition induced by temperature, doping, and pressure are identified using high resolution x-ray absorption spectroscopy at the V pre-K edge. Contrary to what has been taken for granted so far, the metallic phase reached under pressure is shown to differ from the one obtained by changing doping or temperature. Using a novel computational scheme, we relate this effect to the role and occupancy of the a{1g} orbitals. This finding unveils the inequivalence of different routes across the Mott transition in V2O3.
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Affiliation(s)
- F Rodolakis
- Laboratoire de Physique des Solides, CNRS-UMR 8502, Université Paris-Sud, F-91405 Orsay, France
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15
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Hansmann P, Yang X, Toschi A, Khaliullin G, Andersen OK, Held K. Turning a nickelate Fermi surface into a cupratelike one through heterostructuring. Phys Rev Lett 2009; 103:016401. [PMID: 19659160 DOI: 10.1103/physrevlett.103.016401] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Indexed: 05/27/2023]
Abstract
Using the local density approximation and its combination with dynamical mean-field theory, we show that electronic correlations induce a single-sheet, cupratelike Fermi surface for hole-doped 1/1 LaNiO3/LaAlO3 heterostructures, even though both eg orbitals contribute to it. The Ni 3d3z(2)-1} orbital plays the role of the axial Cu 4s-like orbital in the cuprates. These two results indicate that "orbital engineering" by means of heterostructuring should be possible. As we also find strong antiferromagnetic correlations, the low-energy electronic and spin excitations in nickelate heterostructures resemble those of high-temperature cuprate superconductors.
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Affiliation(s)
- P Hansmann
- Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
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16
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Hansmann P, Severing A, Hu Z, Haverkort MW, Chang CF, Klein S, Tanaka A, Hsieh HH, Lin HJ, Chen CT, Fåk B, Lejay P, Tjeng LH. Determining the crystal-field ground state in rare earth heavy fermion materials using soft-x-ray absorption spectroscopy. Phys Rev Lett 2008; 100:066405. [PMID: 18352496 DOI: 10.1103/physrevlett.100.066405] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Indexed: 05/26/2023]
Abstract
We infer that soft-x-ray absorption spectroscopy is a versatile method for the determination of the crystal-field ground state symmetry of rare earth heavy fermion systems, complementing neutron scattering. Using realistic and universal parameters, we provide a theoretical mapping between the polarization dependence of Ce M(4,5) spectra and the charge distribution of the Ce 4f states. The experimental resolution can be orders of magnitude larger than the 4f crystal-field splitting itself. To demonstrate the experimental feasibility of the method, we investigated CePd2Si2, thereby settling an existing disagreement about its crystal-field ground state.
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Affiliation(s)
- P Hansmann
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Strasse 77, D-50937 Köln, Germany
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17
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18
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Eschbach S, Hofmann CJ, Maier UG, Sitte P, Hansmann P. A eukaryotic genome of 660 kb: electrophoretic karyotype of nucleomorph and cell nucleus of the cryptomonad alga, Pyrenomonas salina. Nucleic Acids Res 1991; 19:1779-81. [PMID: 2030961 PMCID: PMC328104 DOI: 10.1093/nar/19.8.1779] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Cryptomonads are unicellular algae with chloroplasts surrounded by four membranes. Between the inner and the outer pairs of membranes is a narrow plasmatic compartment which contains a nucleus-like organelle called the nucleomorph. Using pulsed field gel electrophoresis it is shown that the nucleomorph of the cryptomonad Pyrenomonas salina contains three linear chromosomes of 195 kb, 225 kb and 240 kb all of which encode rRNAs. Thus, this vestigial nucleus has a haploid genome size of 660 kb, harboring the smallest eukaryotic genome known so far. From the cell nucleus of P. salina at least 20 chromosomes ranging from 230 kb to 3.000 kb were fractionated. Here, the rDNA was detected on a single chromosome of about 2.500 kb.
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Affiliation(s)
- S Eschbach
- Institut für Biologie II, Universität, Freiburg, FRG
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19
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Hansmann P, Eschbach S. Isolation and preliminary characterization of the nucleus and the nucleomorph of a cryptomonad, Pyrenomonas salina. Eur J Cell Biol 1990; 52:373-8. [PMID: 2081536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The cryptomonad cell has presumably arisen by a secondary symbiotic event involving two eukaryotes, and thus is composed of four different DNA-containing compartments (nucleus, nucleomorph, plastid, and mitochondrion). In the present paper, the isolation and quantitative DNA estimation of the host cell nucleus and the nucleomorph, a vestigial eukaryotic nucleus, is presented. In the presence of CaCl2, the host nucleus could be isolated from cells lysed by Triton X-100. For isolation of the nucleomorph, cells were slightly fixed with glutardialdehyde and thereafter, lysed by treatment with proteinase K and Triton X-100, leaving an intact nucleomorph-pyrenoid complex. Nuclei were further purified by isopycnic Percoll density gradient centrifugation. Purity and quality of the two nuclear fractions were checked by means of DAPI-epifluorescence microscopy and electron microscopy. The DNA content of the host nucleus and nucleomorph, determined by the diphenylamine method and by means of quantitative microspectrofluorometry, respectively, was found to be more than 700 times higher in the host nucleus than in the nucleomorph.
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Affiliation(s)
- P Hansmann
- Abteilung Zellbiologie, Universität, Freiburg, Bundesrepublik Deutschland
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20
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Scheer U, Messner K, Hazan R, Raska I, Hansmann P, Falk H, Spiess E, Franke WW. High sensitivity immunolocalization of double and single-stranded DNA by a monoclonal antibody. Eur J Cell Biol 1987; 43:358-71. [PMID: 3305019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
A monoclonal antibody (AK 30-10) is described which specifically reacts with DNA both in double and single-stranded forms but not with other molecules and structures, including deoxyribonucleotides and RNAs. When used in immunocytochemical experiments on tissue sections and permeabilized cultured cells, this antibody detects DNA-containing structures, even when the DNA is present in very small amounts. Examples of high resolution detection include the DNA present in amplified extrachromosomal nucleoli, chromomeres of lampbrush chromosomes, mitochondria, chloroplasts and mycoplasmal particles. In immunoelectron microscopy using the immunogold technique, the DNA was localized in distinct substructures such as the "fibrillar centers" of nucleoli and certain stromal centers in chloroplasts. The antibody also reacts with DNA of chromatin of living cells, as shown by microinjection into cultured mitotic cells and into nuclei of amphibian oocytes. The potential value and the limitations of immunocytochemical DNA detection are discussed.
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21
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Hansmann P. [Theoretical and technological principles in telescopic dentures]. Zahntechnik (Berl) 1987; 28:55-8. [PMID: 3303742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Knoth R, Hansmann P, Sitte P. Chromoplasts of Palisota barteri, and the molecular structure of chromoplast tubules. Planta 1986; 168:167-174. [PMID: 24232018 DOI: 10.1007/bf00402960] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/1986] [Accepted: 02/24/1986] [Indexed: 05/28/2023]
Abstract
Ripe, deep-red fruits of Palisota barteri contain tubulous chromoplasts which develop from unpigmented leucoplasts. These plastids contain, besides large spherical inclusion bodies, numerous osmiophilic globules which, in the course of ripening, frequently show transition states to tubular structures. The tubules contain, in all stages of their development, acylated β-citraurin, which is also the main pigment of Citrus fruits. The tubular structures have been isolated, fragmented by French-pressure treatment, and separated into three fractions on sucrose gradients. The lightest fraction (1.044 g·cm(-3)) contained thick fragments ('saccules') with diameters of 50-60 nm, whereas the heaviest (1.083 g·cm(-3)) consisted of tubules 20-25 nm in diameter. The relative amounts of polar lipids, proteins, and carotenoids of the different fractions are consistent with a molecular structure model of tubules and saccules, according to which a wick of longitudinally oriented carotenoid molecules of variable thickness is coated by a monolayer of polar lipids and proteins. High-resolution 'negative-stainings' showed the surface of the tubules to be covered with globular particles of about 6 nm diameter. The main protein of all fractions is a 30-kDa polypeptide; it is assumed that the particles are oligomers of this specific protein.
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Affiliation(s)
- R Knoth
- Lehrstuhl für Zellbiologie, Biologisches Institut II der Universität, Schänzlestrasse 1, D-7800, Freiburg i.Br., Federal Republic of Germany
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Hansmann P, Falk H, Ronai K, Sitte P. Structure, composition, and distribution of plastid nucleoids in Narcissus pseudonarcissus. Planta 1985; 164:459-472. [PMID: 24248218 DOI: 10.1007/bf00395961] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/1984] [Accepted: 12/08/1984] [Indexed: 06/02/2023]
Abstract
The size, frequency and distribution of the nucleoids of chloroplasts (cl-nucleoids) and chromoplasts (cr-nucleoids) of the daffodil have been investigated in situ using the DNA-specific fluorochrome 4'6-diamidino-2-phenylindole. Chromoplasts contain fewer nucleoids (approx. 4) than chloroplasts (> 10), and larger chromoplasts (cultivated form, approx. 4) contain more than smaller ones (wild type, approx. 2). During chromoplast development the nucleoid number decreases in parallel with the chlorophyll content. Each nucleoid contains 2-3 plastome copies on average. In chloroplasts the nucleoids are evenly distributed, whereas they are peripherally located in chromoplasts. The fine structure of isolated cl-and cr-nucleoids, purified either by Sepharose 4B-CL columns or by metrizamide gradients, was investigated electron microscopically. The cl-nucleoids consist of a central protein-rich core with 'naked' DNA-loops protruding from it. In cr-nucleoids, on the other hand, the total DNA is tightly packed within the proteinaceous core. The protein-containing core region of the nucleoids is made up of knotty and fibrillar sub-structures with diameters of 18 and 37 nm, respectively. After proteinase treatment, or incressing ion concentration, most of the proteins are removed and the DNA is exposed even in the case of cr-nucleoids, the stability of which proved to be greater than that of cl-nucleoids. The chemical composition of isolated plastid nucleoids has been determined qualitatively and quantitatively. Chromoplast-nucleoids contain, relative to the same DNA quantity, about six times as much protein as cl-nucleoids. Accordingly the buoyant density of cr-nucleoids in metrizamide gradients is higher than that of cl-nucleoids. In addition to DNA and protein, RNA could be found in the nucleoid fraction. No pigments were present. The cr-and cl-nucleoids have many identical proteins. There are, however, also characteristic differences in their protein pattern which are possibly related to the different expression of the genomes of chloroplasts and chromoplasts. Nucleoids of both plastid types contain some proteins which also occur in isolated envelope membranes (probably partly in the outer membrane) and thus possibly take part in binding the DNA to membranes.
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Affiliation(s)
- P Hansmann
- Institut für Biologie II, Zellbiologie, Schänzlestrasse 1, D-7800, Freiburg/Brsg., Federal Republic of Germany
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24
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Knoth R, Klein P, Hansmann P. Morphological and chemical studies on the crystalloid-forming 'succulent protein' from normal and ribosome-deficient Aeonium domesticum plastids. Planta 1984; 161:105-112. [PMID: 24253597 DOI: 10.1007/bf00395469] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/1983] [Accepted: 12/27/1983] [Indexed: 06/02/2023]
Abstract
Aeonium domesticum cv. variegatum is a mesochimera of the constitution green/white/green with normal proplastids and chloroplasts in the unaffected tissues and ribosome-deficient colourless mutant plastids in the white leaf tissues. All the different plastid types contain 'succulent protein crystalloids' (SPC). For more detailed characterization, the SPC elements were freed from the plastids and purified by gel filtration. Electron microscopy of different fractions revealed five levels of structural organization. Beginning with the most complex state, the levels are designated as 'succulent protein (SP) organizational state' V (hexagonally arranged and closely packed tubules in the stroma of intact plastids) to I (globular protomers of 5 nm diameter as the basic structure of SPCs). Highly purified SP-fractions were shown by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to consist of two or three proteins of Mr 56 kdalton, 58 kdalton and 60 kdalton, depending on the buffer medium used for SP isolation and the duration of storage of leaves in the frozen state. In the urea/SDS-PAGE system, these proteins show similar mobilities to α- and β-tubulin, but no immunoreaction against antitubulin. The proteolytic cleavage pattern of tubulin subunits and SP proteins are different. Their locations on two-dimensional isoelectric focusing-SDS gels show some overlappings because of microheterogeneities in both proteins in the pH gradient from pH 4.5 to 6.5. Malatedehydrogenase activity could not be detected in the purified SP fractions.
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Affiliation(s)
- R Knoth
- Lehrstuhl für Zellbiologie, Biologisches Institut II der Universität, Schänzlestraße 1, D-7800, Freiburg i. Br., Federal Republic of Germany
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25
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Hansmann P, Sitte P. Composition and molecular structure of chromoplast globules of Viola tricolor. Plant Cell Rep 1982; 1:111-114. [PMID: 24259022 DOI: 10.1007/bf00272366] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/1982] [Indexed: 06/02/2023]
Abstract
Plastoglobules have been isolated in pure form from petals of the pansy, Viola tricolor L. Their chemical composition has been determined up to a recovery of 96% dry weight. Triacyl glycerols (57%) as well as carotenoids and their esters (23%) are the main constituents. Polar lipids, proteins, alkanes, phytyl esters, plastid quinones, and steryl esters have been detected in smaller amounts (cf. Table 1). The mean diameter of chromoplast globules is 280±70 nm (corresponding to a volume of 11.7×10(6) nm(3)), their buoyant density 0.93 g cm(-3). The plastoglobules are devoid of a surrounding unit membrane. However, electron microscopical evidence and analytical data are consistent with a structural model envisaging the globules to consist mainly of an apolar core, covered by a 'half unit membrane' of polar constituents.
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Affiliation(s)
- P Hansmann
- Institut für Biologie II, Zellbiologie, Universität Freiburg, Schänzlestraße 1, D-7800, Freiburg i. Br., Federal Republic of Germany
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