Direct evidence of non-Zhang-Rice Cu3+ centers in La2Li0.5Cu0.5O4 / Moskvin A. S.,Gippius A. A.,Tkachev A. V.,Mahajan A. V.,Chakrabarty T.,Presniakov I. A.,Sobolev A. V.,Demazeau G. // PHYSICAL REVIEW B. - 2012. - V. 86, l. 24.

ISSN/EISSN:

1098-0121 / нет данных

Type:

Article

Abstract:

A well-isolated Zhang-Rice (ZR) singlet as a ground state of the Cu3+ center in hole-doped cuprates is a leading paradigm in modern theories of high-temperature superconductivity. However, a dramatic temperature evolution of the Li-6,Li-7 NMR signal in La2Li0.5Cu0.5O4, a system with a regular lattice of well-isolated Cu3+ centers, reveals significant magnetic fluctuations and suggests a quasidegeneracy to be a generic property of their ground state at variance with the simple ZR model. We argue for a competition of the ZR state with nearby states formed by a ``doped{''} hole occupying purely oxygen nonbonding a(2g)(pi) and e(u)(pi) orbitals rather than a conventional b(1g)(d(x2-y2))Cu 3d-O 2p hybrid. The temperature variation of the Li-6,Li-7 NMR line shape and spin-lattice relaxation rate point to a gradual slowing down of some magnetic order parameter's fluctuations without distinct signatures of a phase transition down to T = 2 K. This behavior agrees with a stripelike ferrodistortive fluctuating Ammm order in a two-dimensional structure of the (CuLi)O-2 planes accompanied by unconventional oxygen orbital antiferromagnetic fluctuations. DOI: 10.1103/PhysRevB.86.241107

Author keywords:

MAGNETIC EXCITATIONS; LA2CU0.5LI0.5O4; COPPER; STATE; SUPERCONDUCTORS; LA2CU1-XLIXO4; SINGLET; OXIDES; PHASES

DOI:

10.1103/PhysRevB.86.241107

Web of Science ID:

ISI:000312365800002

Соавторы в МНС:

—

Другие поля

Поле	Значение
Month	DEC 17
Publisher	AMER PHYSICAL SOC
Address	ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
Language	English
Article-Number	241107
Keywords-Plus	MAGNETIC EXCITATIONS; LA2CU0.5LI0.5O4; COPPER; STATE; SUPERCONDUCTORS; LA2CU1-XLIXO4; SINGLET; OXIDES; PHASES
Research-Areas	Physics
Web-of-Science-Categories	Physics, Condensed Matter
ResearcherID-Numbers	Gippius, Andrey/D-1139-2010 Sobolev, Alexey/C-3832-2009 Presniakov, Igor/B-8752-2009
ORCID-Numbers	Sobolev, Alexey/0000-0002-8085-5425 Mahajan, Avinash/0000-0003-3241-6660
Funding-Acknowledgement	RFBR {[}10-02-96032, 12-02-01039]; Joint Russian-Indian RFFI-DST {[}11-02-92707-IND]
Funding-Text	Discussions with S.-L. Drechsler, R. Hayn, J. Haase, and H. Alloul are gratefully acknowledged. The RFBR {[}Grants No. 10-02-96032 and No. 12-02-01039 (A. S. M.)] and the Joint Russian-Indian RFFI-DST Grant No. 11-02-92707-IND (A. A. G., A. V. T., A. V. M., and T. C.) are acknowledged for providing financial support.
Number-of-Cited-References	17
Usage-Count-Last-180-days	2
Usage-Count-Since-2013	21
Journal-ISO	Phys. Rev. B
Doc-Delivery-Number	054TG