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Title: Spin fluctuations and covalence in neutron Bragg scattering from YBa sub 2 Cu sub 3 O sub 6 and La sub 2 CuO sub 4

Abstract

A puzzle is pointed out concerning the low-temperature behavlor of La{sub 2}CuO{sub 4} and YBa{sub 2}Cu{sub 3}O{sub 6,} the insulating parents'' of the high-{ital T}{sub {ital c}} superconductors, and indicate a possible solution. The measured ordered magnetic moment is about 0.64 {mu}{sub {ital B}} per Cu, in agreement with the value calculated on the basis of the Heisenberg Hamiltonian. But this calculation is within a nearly purely ionic or localized picture of the Cu {ital d} hole, the reduction from 1.1 {mu}{sub {ital B}} ({ital g}{approx}2.2) being entirely due to spin fluctuations. Thus the almost perfect agreement leaves no room for the moment reduction due to covalence or 3{ital d}-2{ital p} hybridization, expected to be large in these oxides. A possible explanation might lie in the fact that an ostensibly symmetry-based argument relating the calculated moment (in the symmetry-unbroken state) to that measured is not valid, as has recently been shown.

Authors:
;  [1]
  1. Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (USA) Center for Fundamental Materials Research, Michigan State University, East Lansing, Michigan 48824 (USA)
Publication Date:
OSTI Identifier:
5623250
Resource Type:
Journal Article
Journal Name:
Journal of Applied Physics; (USA)
Additional Journal Information:
Journal Volume: 69:8; Journal ID: ISSN 0021-8979
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BARIUM OXIDES; NEUTRON DIFFRACTION; COPPER OXIDES; LANTHANUM OXIDES; YTTRIUM OXIDES; COVALENCE; HYBRIDIZATION; MAGNETIC MOMENTS; MAGNETIC PROPERTIES; SYMMETRY; ALKALINE EARTH METAL COMPOUNDS; BARIUM COMPOUNDS; CHALCOGENIDES; COHERENT SCATTERING; COPPER COMPOUNDS; DIFFRACTION; LANTHANUM COMPOUNDS; OXIDES; OXYGEN COMPOUNDS; PHYSICAL PROPERTIES; RARE EARTH COMPOUNDS; SCATTERING; TRANSITION ELEMENT COMPOUNDS; YTTRIUM COMPOUNDS; 360204* - Ceramics, Cermets, & Refractories- Physical Properties

Citation Formats

Kaplan, T A, and Mahanti, S D. Spin fluctuations and covalence in neutron Bragg scattering from YBa sub 2 Cu sub 3 O sub 6 and La sub 2 CuO sub 4. United States: N. p., 1991. Web. doi:10.1063/1.348039.
Kaplan, T A, & Mahanti, S D. Spin fluctuations and covalence in neutron Bragg scattering from YBa sub 2 Cu sub 3 O sub 6 and La sub 2 CuO sub 4. United States. https://doi.org/10.1063/1.348039
Kaplan, T A, and Mahanti, S D. 1991. "Spin fluctuations and covalence in neutron Bragg scattering from YBa sub 2 Cu sub 3 O sub 6 and La sub 2 CuO sub 4". United States. https://doi.org/10.1063/1.348039.
@article{osti_5623250,
title = {Spin fluctuations and covalence in neutron Bragg scattering from YBa sub 2 Cu sub 3 O sub 6 and La sub 2 CuO sub 4},
author = {Kaplan, T A and Mahanti, S D},
abstractNote = {A puzzle is pointed out concerning the low-temperature behavlor of La{sub 2}CuO{sub 4} and YBa{sub 2}Cu{sub 3}O{sub 6,} the insulating parents'' of the high-{ital T}{sub {ital c}} superconductors, and indicate a possible solution. The measured ordered magnetic moment is about 0.64 {mu}{sub {ital B}} per Cu, in agreement with the value calculated on the basis of the Heisenberg Hamiltonian. But this calculation is within a nearly purely ionic or localized picture of the Cu {ital d} hole, the reduction from 1.1 {mu}{sub {ital B}} ({ital g}{approx}2.2) being entirely due to spin fluctuations. Thus the almost perfect agreement leaves no room for the moment reduction due to covalence or 3{ital d}-2{ital p} hybridization, expected to be large in these oxides. A possible explanation might lie in the fact that an ostensibly symmetry-based argument relating the calculated moment (in the symmetry-unbroken state) to that measured is not valid, as has recently been shown.},
doi = {10.1063/1.348039},
url = {https://www.osti.gov/biblio/5623250}, journal = {Journal of Applied Physics; (USA)},
issn = {0021-8979},
number = ,
volume = 69:8,
place = {United States},
year = {Mon Apr 15 00:00:00 EDT 1991},
month = {Mon Apr 15 00:00:00 EDT 1991}
}