Electronic inhomogeneity and possible pseudogap behavior of spin susceptibility in the electron-doped superconductor Sr0.93la0.07CuO2:63Cu NMR study

S. Verkhovskii; K. Mikhalev; A. Gerashenko; Y. Piskunov; V. Kazantsev; V. Bobrovskii; E. Mitberg; A. Podlesnyak; A. Mirmelstein

Electronic inhomogeneity and possible pseudogap behavior of spin susceptibility in the electron-doped superconductor Sr_0.93la_0.07CuO₂:⁶³Cu NMR study

S. Verkhovskii, K. Mikhalev, A. Gerashenko, Y. Piskunov, V. Kazantsev, V. Bobrovskii, E. Mitberg, A. Podlesnyak, A. Mirmelstein

Research output: Contribution to journal › Article › peer-review

4 Scopus citations

Abstract

The magnetic susceptibility, NMR spectra, nuclear spin-lattice relaxation rate (T1^-1)α and the echo-decay rate (T₂^-1) of ⁶³Cu were measured for the electron-doped infinite-layer superconductor Sr_0.93La_0.07CuO₂/T_c^onset = 42.4 K). The results obtained revealed a clear tendency toward frustrated phase separation in this nominally underdoped high-T_c material. Above T_c the ⁶³Cu Knight shift is found to decrease upon cooling giving an evidence for a pseudogaplike decrease of the spin susceptibility. It is shown that unusual anisotropy of the ⁶³Cu Knight shift in the electron-doped CuO₂ layer can be understood as a "compensation effect" between the Isotropie hyperfine coupling, mediated by the 4s Fermi-contact and 3d core-polarization exchange interactions, and the anisotropic on-site spin-dipolar hyperfine interaction of the Cu nuclei with the itinerant carriers, whose states near the Fermi energy have a sizeable admixture of Cu(4p_z) and/or Cu(3d_z²) orbitals.

Original language	English
Pages (from-to)	543-554
Number of pages	12
Journal	Journal of Superconductivity and Novel Magnetism
Volume	16
Issue number	3
State	Published - 2003
Externally published	Yes

Funding

The authors thank E. Khlybov, I. Kostyleva, and L. Bogacheva for collaboration in sample synthesis, A. Furrer for his fruitful discussions, and B. Goshchitskii for his support of this research. Financial Support by INTAS (project No. 99-0256), RFBR (grant No. 03-02-16673), Special Federal Program of basic researches at Russian Academy of Science “Quantum Macrophysics” (contract No. 25/02) and Russian State Program “Superconductivity” (State contract no. 107-1(00)-P-D01, agreement No. 7/01) is gratefully acknowledged.

Funders	Funder number
INTAS	99-0256
Russian State Program	7/01, 107-1(00)-P-D01
Russian Foundation for Basic Research	03-02-16673
Russian Foundation for Basic Research
Russian Academy of Sciences	25/02
Russian Academy of Sciences

Keywords

Electron-doped high-Tsuperconductors
Electronic inhomogeneity
NMR
Pseudogap

Cite this

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title = "Electronic inhomogeneity and possible pseudogap behavior of spin susceptibility in the electron-doped superconductor Sr0.93la0.07CuO2:63Cu NMR study",

abstract = "The magnetic susceptibility, NMR spectra, nuclear spin-lattice relaxation rate (T1-1)α and the echo-decay rate (T2-1) of 63Cu were measured for the electron-doped infinite-layer superconductor Sr0.93La0.07CuO2/Tconset = 42.4 K). The results obtained revealed a clear tendency toward frustrated phase separation in this nominally underdoped high-Tc material. Above Tc the 63Cu Knight shift is found to decrease upon cooling giving an evidence for a pseudogaplike decrease of the spin susceptibility. It is shown that unusual anisotropy of the 63Cu Knight shift in the electron-doped CuO2 layer can be understood as a {"}compensation effect{"} between the Isotropie hyperfine coupling, mediated by the 4s Fermi-contact and 3d core-polarization exchange interactions, and the anisotropic on-site spin-dipolar hyperfine interaction of the Cu nuclei with the itinerant carriers, whose states near the Fermi energy have a sizeable admixture of Cu(4pz) and/or Cu(3dz2) orbitals.",

keywords = "Electron-doped high-Tsuperconductors, Electronic inhomogeneity, NMR, Pseudogap",

author = "S. Verkhovskii and K. Mikhalev and A. Gerashenko and Y. Piskunov and V. Kazantsev and V. Bobrovskii and E. Mitberg and A. Podlesnyak and A. Mirmelstein",

year = "2003",

language = "English",

volume = "16",

pages = "543--554",

journal = "Journal of Superconductivity and Novel Magnetism",

issn = "1557-1939",

publisher = "Springer",

number = "3",

}

TY - JOUR

T1 - Electronic inhomogeneity and possible pseudogap behavior of spin susceptibility in the electron-doped superconductor Sr0.93la0.07CuO2:63Cu NMR study

AU - Verkhovskii, S.

AU - Mikhalev, K.

AU - Gerashenko, A.

AU - Piskunov, Y.

AU - Kazantsev, V.

AU - Bobrovskii, V.

AU - Mitberg, E.

AU - Podlesnyak, A.

AU - Mirmelstein, A.

PY - 2003

Y1 - 2003

N2 - The magnetic susceptibility, NMR spectra, nuclear spin-lattice relaxation rate (T1-1)α and the echo-decay rate (T2-1) of 63Cu were measured for the electron-doped infinite-layer superconductor Sr0.93La0.07CuO2/Tconset = 42.4 K). The results obtained revealed a clear tendency toward frustrated phase separation in this nominally underdoped high-Tc material. Above Tc the 63Cu Knight shift is found to decrease upon cooling giving an evidence for a pseudogaplike decrease of the spin susceptibility. It is shown that unusual anisotropy of the 63Cu Knight shift in the electron-doped CuO2 layer can be understood as a "compensation effect" between the Isotropie hyperfine coupling, mediated by the 4s Fermi-contact and 3d core-polarization exchange interactions, and the anisotropic on-site spin-dipolar hyperfine interaction of the Cu nuclei with the itinerant carriers, whose states near the Fermi energy have a sizeable admixture of Cu(4pz) and/or Cu(3dz2) orbitals.

AB - The magnetic susceptibility, NMR spectra, nuclear spin-lattice relaxation rate (T1-1)α and the echo-decay rate (T2-1) of 63Cu were measured for the electron-doped infinite-layer superconductor Sr0.93La0.07CuO2/Tconset = 42.4 K). The results obtained revealed a clear tendency toward frustrated phase separation in this nominally underdoped high-Tc material. Above Tc the 63Cu Knight shift is found to decrease upon cooling giving an evidence for a pseudogaplike decrease of the spin susceptibility. It is shown that unusual anisotropy of the 63Cu Knight shift in the electron-doped CuO2 layer can be understood as a "compensation effect" between the Isotropie hyperfine coupling, mediated by the 4s Fermi-contact and 3d core-polarization exchange interactions, and the anisotropic on-site spin-dipolar hyperfine interaction of the Cu nuclei with the itinerant carriers, whose states near the Fermi energy have a sizeable admixture of Cu(4pz) and/or Cu(3dz2) orbitals.

KW - Electron-doped high-Tsuperconductors

KW - Electronic inhomogeneity

KW - NMR

KW - Pseudogap

UR - http://www.scopus.com/inward/record.url?scp=0346198663&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0346198663

SN - 1557-1939

VL - 16

SP - 543

EP - 554

JO - Journal of Superconductivity and Novel Magnetism

JF - Journal of Superconductivity and Novel Magnetism

IS - 3

ER -

Electronic inhomogeneity and possible pseudogap behavior of spin susceptibility in the electron-doped superconductor Sr_0.93la_0.07CuO₂:⁶³Cu NMR study

Abstract

Funding

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