Ivanović, Aleksandra

[["dc.bibliographiccitation.artnumber","037207"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Physical Review Letters"],["dc.bibliographiccitation.volume","105"],["dc.contributor.author","Suchaneck, A."],["dc.contributor.author","Hinkov, V."],["dc.contributor.author","Haug, D."],["dc.contributor.author","Schulz, L."],["dc.contributor.author","Bernhard, C."],["dc.contributor.author","Ivanov, A."],["dc.contributor.author","Hradil, Klaudia"],["dc.contributor.author","Lin, C. T."],["dc.contributor.author","Bourges, Philippe"],["dc.contributor.author","Keimer, B."],["dc.contributor.author","Sidis, Y."],["dc.date.accessioned","2018-11-07T08:41:20Z"],["dc.date.available","2018-11-07T08:41:20Z"],["dc.date.issued","2010"],["dc.description.abstract","We report an inelastic-neutron-scattering and muon-spin-relaxation study of the effect of 2% spinless (Zn) impurities on the magnetic order and dynamics of YBa2Cu3O6.6, an underdoped high-temperature superconductor that exhibits a prominent spin pseudogap in its normal state. Zn substitution induces static magnetic order at low temperatures and triggers a large-scale spectral-weight redistribution from the magnetic resonant mode at 38 meV into uniaxial, incommensurate spin excitations with energies well below the spin pseudogap. These observations indicate a competition between incommensurate magnetic order and superconductivity close to a quantum critical point. Comparison to prior data on La2-xSrxCuO4 suggests that this behavior is universal for the layered copper oxides and analogous to impurity-induced magnetic order in one-dimensional quantum magnets."],["dc.description.sponsorship","DFG [FOR538]"],["dc.identifier.doi","10.1103/PhysRevLett.105.037207"],["dc.identifier.isi","000280008900019"],["dc.identifier.pmid","20867803"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/19444"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Physical Soc"],["dc.relation.issn","0031-9007"],["dc.title","Incommensurate Magnetic Order and Dynamics Induced by Spinless Impurities in YBa2Cu3O6.6"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","214512"],["dc.bibliographiccitation.issue","21"],["dc.bibliographiccitation.journal","PHYSICAL REVIEW B"],["dc.bibliographiccitation.volume","76"],["dc.contributor.author","Fauque, B."],["dc.contributor.author","Sidis, Y."],["dc.contributor.author","Capogna, L."],["dc.contributor.author","Ivanov, A."],["dc.contributor.author","Hradil, Klaudia"],["dc.contributor.author","Ulrich, Cornelia M."],["dc.contributor.author","Rykov, A. I."],["dc.contributor.author","Keimer, B."],["dc.contributor.author","Bourges, Philippe"],["dc.date.accessioned","2018-11-07T10:50:18Z"],["dc.date.available","2018-11-07T10:50:18Z"],["dc.date.issued","2007"],["dc.description.abstract","We report a neutron scattering study of the spin excitation spectrum in the superconducting state of the slightly overdoped Bi2Sr2CaCu2O8+delta system (T-c= 87 K). We focus on the dispersion of the resonance peak in the superconducting state that is due to a S= 1 collective mode. The measured spin excitation spectrum bears a strong similarity to the spectrum of the YBa(2)Cu(3)On(6+x) system for a similar doping level (i.e., x similar to 0.95-1), which can be described as intersecting upward- and downward-dispersing branches. A close comparison of the threshold of the electron-hole spin flip continuum, known from angle resolved photoemission measurements in the same system, indicates that the magnetic response in the superconducting state is confined, in both energy and momentum, below the gapped Stoner continuum. In contrast to YBa2Cu3O6+x, the spin excitation spectrum is broader than the experimental resolution. In the framework of an itinerant-electron model, we quantitatively relate this intrinsic energy width to the superconducting gap distribution observed in scanning tunneling microscopy experiments. Our study further suggests a significant in-plane anisotropy of the magnetic response."],["dc.identifier.doi","10.1103/PhysRevB.76.214512"],["dc.identifier.isi","000251986100096"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/48624"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Physical Soc"],["dc.relation.issn","2469-9969"],["dc.relation.issn","2469-9950"],["dc.title","Dispersion of the odd magnetic resonant mode in near-optimally doped Bi2Sr2CaCu2O8+delta"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","134503"],["dc.bibliographiccitation.issue","13"],["dc.bibliographiccitation.journal","PHYSICAL REVIEW B"],["dc.bibliographiccitation.volume","82"],["dc.contributor.author","Park, J. T."],["dc.contributor.author","Inosov, D. S."],["dc.contributor.author","Yaresko, A."],["dc.contributor.author","Graser, S."],["dc.contributor.author","Sun, D. L."],["dc.contributor.author","Bourges, Philippe"],["dc.contributor.author","Sidis, Y."],["dc.contributor.author","Li, Yuan"],["dc.contributor.author","Kim, J.-H."],["dc.contributor.author","Haug, D."],["dc.contributor.author","Ivanov, A."],["dc.contributor.author","Hradil, Klaudia"],["dc.contributor.author","Schneidewind, Astrid"],["dc.contributor.author","Link, P."],["dc.contributor.author","Faulhaber, Enrico"],["dc.contributor.author","Glavatskyy, I."],["dc.contributor.author","Lin, C. T."],["dc.contributor.author","Keimer, B."],["dc.contributor.author","Hinkov, V."],["dc.date.accessioned","2018-11-07T08:38:55Z"],["dc.date.available","2018-11-07T08:38:55Z"],["dc.date.issued","2010"],["dc.description.abstract","We study the symmetry of spin excitation spectra in 122-ferropnictide superconductors by comparing the results of first-principles calculations with inelastic neutron-scattering (INS) measurements on BaFe1.85Co0.15As2 and BaFe1.91Ni0.09As2 samples that exhibit neither static magnetic phases nor structural phase transitions. In both the normal and superconducting (SC) states, the spectrum lacks the three-dimensional 4(2)/m screw symmetry around the (1/2 1/2 L) axis that is implied by the I4/mmm space group. This is manifest both in the in-plane anisotropy of the normal- and SC-state spin dynamics and in the out-of-plane dispersion of the spin-resonance mode. We show that this effect originates from the higher symmetry of the magnetic Fe sublattice with respect to the crystal itself, hence the INS signal inherits the symmetry of the unfolded Brillouin zone (BZ) of the Fe sublattice. The in-plane anisotropy is temperature independent and can be qualitatively reproduced in normal-state density-functional-theory calculations without invoking a symmetry-broken (\"nematic\") ground state that was previously proposed as an explanation for this effect. Below the SC transition, the energy of the magnetic resonant mode omega(res), as well as its intensity and the SC spin gap inherit the normal-state intensity modulation along the out-of-plane direction L with a period twice larger than expected from the body-centered-tetragonal BZ symmetry. The amplitude of this modulation decreases at higher doping, providing an analogy to the splitting between even and odd resonant modes in bilayer cuprates. Combining our and previous data, we show that at odd L a universal linear relationship (h) over bar omega(res) approximate to 4.3 k(B)T(c) holds for all the studied Fe-based superconductors, independent of their carrier type. Its validity down to the lowest doping levels is consistent with weaker electron correlations in ferropnictides as compared to the underdoped cuprates."],["dc.description.sponsorship","DFG [1458, BO3537/1-1]"],["dc.identifier.doi","10.1103/PhysRevB.82.134503"],["dc.identifier.isi","000282358900007"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/18868"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Physical Soc"],["dc.relation.issn","1098-0121"],["dc.title","Symmetry of spin excitation spectra in the tetragonal paramagnetic and superconducting phases of 122-ferropnictides"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]