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Gotter R, Verna A, Sbroscia M, Moroni R, Bisio F, Iacobucci S, Offi F, Vaidya SR, Ruocco A, Stefani G. Unexpectedly Large Electron Correlation Measured in Auger Spectra of Ferromagnetic Iron Thin Films: Orbital-Selected Coulomb and Exchange Contributions. Phys Rev Lett 2020; 125:067202. [PMID: 32845695 DOI: 10.1103/physrevlett.125.067202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/08/2020] [Indexed: 06/11/2023]
Abstract
A set of electron-correlation energies as large as 10 eV have been measured for a magnetic 2 ML Fe film deposited on Ag(001). By exploiting the spin selectivity in angle-resolved Auger-photoelectron coincidence spectroscopy and the Cini-Sawatzky theory, the core-valence-valence Auger spectrum of a spin-polarized system have been resolved: correlation energies have been determined for each individual combination of the two holes created in the four subbands involved in the decay: majority and minority spin, as well as e_{g} and t_{2g}. The energy difference between final states with parallel and antiparallel spin of the two emitted electrons is ascribed to the spin-flip energy for the final ion state, thus disentangling the contributions of Coulomb and exchange interactions.
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Affiliation(s)
- R Gotter
- CNR-IOM, Istituto Officina dei Materiali, c/o Area Science Park, SS14 km 163,5 I-34149 Basovizza-Trieste, Italy
| | - A Verna
- Dipartimento di Scienze, Università degli Studi Roma Tre, Via della Vasca Navale 84, I-00146 Rome, Italy
| | - M Sbroscia
- Dipartimento di Scienze, Università degli Studi Roma Tre, Via della Vasca Navale 84, I-00146 Rome, Italy
| | - R Moroni
- CNR-SPIN, Corso Perrone 24, I-16152 Genova, Italy
| | - F Bisio
- CNR-SPIN, Corso Perrone 24, I-16152 Genova, Italy
| | - S Iacobucci
- Dipartimento di Scienze, Università degli Studi Roma Tre, Via della Vasca Navale 84, I-00146 Rome, Italy
- CNR-ISM, Via Fosso del Cavaliere 100, 00133 Roma, Italy
| | - F Offi
- Dipartimento di Scienze, Università degli Studi Roma Tre, Via della Vasca Navale 84, I-00146 Rome, Italy
| | - S R Vaidya
- CNR-IOM, Istituto Officina dei Materiali, c/o Area Science Park, SS14 km 163,5 I-34149 Basovizza-Trieste, Italy
- Scuola di Dottorato in Nanotecnologie, Università di Trieste, Piazzale Europa 1, I-34127 Trieste, Italy
| | - A Ruocco
- Dipartimento di Scienze, Università degli Studi Roma Tre, Via della Vasca Navale 84, I-00146 Rome, Italy
| | - G Stefani
- Dipartimento di Scienze, Università degli Studi Roma Tre, Via della Vasca Navale 84, I-00146 Rome, Italy
- CNR-ISM, Via Fosso del Cavaliere 100, 00133 Roma, Italy
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Cini M, Perfetto E, Gotter R, Offi F, Ruocco A, Stefani G. Insight on hole-hole interaction and magnetic order from dichroic auger-photoelectron coincidence spectra. Phys Rev Lett 2011; 107:217602. [PMID: 22181926 DOI: 10.1103/physrevlett.107.217602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Indexed: 05/31/2023]
Abstract
The absence of sharp structures in the Auger line shapes of partially filled bands has severely limited the use of electron spectroscopy in magnetic crystals and other correlated materials. By a novel interplay of experimental and theoretical techniques we achieve a combined understanding of the photoelectron, Auger, and Auger-photoelectron coincidence spectra (APECS) of the antiferromagnetic CoO. A recently discovered dichroic effect in angle resolved (DEAR) APECS reveals a complex pattern in the Auger line shape, which is here explained in detail, labeling the final states by their total spin. Since the dichroic effect exists in the antiferromagnetic state but vanishes at the Néel temperature, the DEAR-APECS technique detects the phase transition from its local effects, thus providing a unique tool to observe and understand magnetic correlations where the usual methods are not applicable.
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Affiliation(s)
- M Cini
- Dipartimento di Fisica, Università di Roma Tor Vergata, Rome, Italy
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Affiliation(s)
- G. Dalba
- a Dipartimento di Fisica , Universitá di Trento. , I-38050 , Povo, Trento , Italy
| | - P. Fornasini
- a Dipartimento di Fisica , Universitá di Trento. , I-38050 , Povo, Trento , Italy
| | - R. Gotter
- a Dipartimento di Fisica , Universitá di Trento. , I-38050 , Povo, Trento , Italy
| | - M. Grazioli
- a Dipartimento di Fisica , Universitá di Trento. , I-38050 , Povo, Trento , Italy
| | - F. Rocca
- b Centro di Fisica degli Stati Aggregati ed Impianto Ionico del Consiglio Nazionale delle Richerche e Istituto Trentino di Culture , I-38050 , Povo, Trento , Italy
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Pardini T, Cepek C, Larciprete R, Sangaletti L, Pagliara S, Gotter R, Floreano L, Verdini A, Morgante A, Parmigiani F, Goldoni A. Electronic properties of a pure and sodium-doped C70 single layer adsorbed on Al polycrystalline surface. J Chem Phys 2005; 122:54704. [PMID: 15740343 DOI: 10.1063/1.1834494] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Core level and valence band photoemission measurements combined with near edge x-ray absorption fine structure measurements were performed on a single C(70) layer adsorbed on polycrystalline Al (1 ML-C(70)/Al) (ML-monolayer), pure and doped with sodium atoms. The data obtained from the pure ML chemisorbed on Al surface show a semiconducting behavior of the system, which is characterized by a covalent bond between the adsorbate and the substrate. The same data show also that the C(70) molecules tend to orient themselves with the C(5v) axis perpendicular to the surface in analogy to what observed for 1 ML-C(70)/Cu(111). By doping the sample with sodium atoms a charge transfer from the alkali atoms to the lowest unoccupied molecular orbital (LUMO) of the C(70) molecules takes place, as underlined by the gradual increasing intensity of the C(70) LUMO peak as a function of doping. Nevertheless, no metallic phases are observed for any doping step.
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Affiliation(s)
- T Pardini
- Dipartimento di Fisica, Università di Trieste, Via Valerio 2, 34127 Trieste, Italy
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Cossaro A, Cvetko D, Bavdek G, Floreano L, Gotter R, Morgante A, Evangelista F, Ruocco A. Copper−Phthalocyanine Induced Reconstruction of Au(110). J Phys Chem B 2004. [DOI: 10.1021/jp049108h] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- A. Cossaro
- Laboratorio TASC dell'Istituto Nazionale per la Fisica della Materia, Basovizza SS-14, Km 163.5, I-34012 Trieste, Italy, Department of Physics, University of Ljubljana, Ljubljana, Slovenia, Jožef Stefan Institute, Ljubljana, Slovenia, Department of Physics, University of Trieste, Trieste, Italy, INFM unit of Roma Tre and Physics Department, University of Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy
| | - D. Cvetko
- Laboratorio TASC dell'Istituto Nazionale per la Fisica della Materia, Basovizza SS-14, Km 163.5, I-34012 Trieste, Italy, Department of Physics, University of Ljubljana, Ljubljana, Slovenia, Jožef Stefan Institute, Ljubljana, Slovenia, Department of Physics, University of Trieste, Trieste, Italy, INFM unit of Roma Tre and Physics Department, University of Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy
| | - G. Bavdek
- Laboratorio TASC dell'Istituto Nazionale per la Fisica della Materia, Basovizza SS-14, Km 163.5, I-34012 Trieste, Italy, Department of Physics, University of Ljubljana, Ljubljana, Slovenia, Jožef Stefan Institute, Ljubljana, Slovenia, Department of Physics, University of Trieste, Trieste, Italy, INFM unit of Roma Tre and Physics Department, University of Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy
| | - L. Floreano
- Laboratorio TASC dell'Istituto Nazionale per la Fisica della Materia, Basovizza SS-14, Km 163.5, I-34012 Trieste, Italy, Department of Physics, University of Ljubljana, Ljubljana, Slovenia, Jožef Stefan Institute, Ljubljana, Slovenia, Department of Physics, University of Trieste, Trieste, Italy, INFM unit of Roma Tre and Physics Department, University of Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy
| | - R. Gotter
- Laboratorio TASC dell'Istituto Nazionale per la Fisica della Materia, Basovizza SS-14, Km 163.5, I-34012 Trieste, Italy, Department of Physics, University of Ljubljana, Ljubljana, Slovenia, Jožef Stefan Institute, Ljubljana, Slovenia, Department of Physics, University of Trieste, Trieste, Italy, INFM unit of Roma Tre and Physics Department, University of Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy
| | - A. Morgante
- Laboratorio TASC dell'Istituto Nazionale per la Fisica della Materia, Basovizza SS-14, Km 163.5, I-34012 Trieste, Italy, Department of Physics, University of Ljubljana, Ljubljana, Slovenia, Jožef Stefan Institute, Ljubljana, Slovenia, Department of Physics, University of Trieste, Trieste, Italy, INFM unit of Roma Tre and Physics Department, University of Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy
| | - F. Evangelista
- Laboratorio TASC dell'Istituto Nazionale per la Fisica della Materia, Basovizza SS-14, Km 163.5, I-34012 Trieste, Italy, Department of Physics, University of Ljubljana, Ljubljana, Slovenia, Jožef Stefan Institute, Ljubljana, Slovenia, Department of Physics, University of Trieste, Trieste, Italy, INFM unit of Roma Tre and Physics Department, University of Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy
| | - A. Ruocco
- Laboratorio TASC dell'Istituto Nazionale per la Fisica della Materia, Basovizza SS-14, Km 163.5, I-34012 Trieste, Italy, Department of Physics, University of Ljubljana, Ljubljana, Slovenia, Jožef Stefan Institute, Ljubljana, Slovenia, Department of Physics, University of Trieste, Trieste, Italy, INFM unit of Roma Tre and Physics Department, University of Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy
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