Interplay of p-d and d-d charge transfer transitions in rare-earth perovskite manganites / Moskvin A. S.,Makhnev A. A.,Nomerovannaya L. V.,Loshkareva N. N.,Balbashov A. M. // PHYSICAL REVIEW B. - 2010. - V. 82, l. 3.

ISSN/EISSN:

2469-9950 / 2469-9969

Type:

Article

Abstract:

We have performed both theoretical and experimental studies of optical response of parent perovskite manganites RMnO3 with a main goal to elucidate nature of clearly visible optical features. Starting with a simple cluster model approach we addressed the both one-center (p-d) and two-center (d-d) charge transfer (CT) transitions, their polarization properties, the role played by structural parameters, orbital mixing, and spin degree of freedom. Optical complex dielectric function of single-crystalline samples of RMnO3 (R=La, Pr, Nd, Sm, Eu) was measured by ellipsometric technique at room temperature in the spectral range from 1.0 to 5.0 eV for two light polarizations: E parallel to c and E perpendicular to c. The comparative analysis of the spectral behavior of epsilon(1) and epsilon(2) is believed to provide a more reliable assignment of spectral features. We have found an overall agreement between experimental spectra and theoretical predictions based on the theory of one-center p-d CT transitions and intersite d-d CT transitions. Our experimental data and theoretical analysis evidence a dual nature of the dielectric gap in nominally stoichiometric matrix of perovskite manganites RMnO3, it is formed by a superposition of forbidden or weak dipole allowed p-d CT transitions and intersite d-d CT transitions. In fact, the parent perovskite manganites RMnO3 should rather be sorted neither into the CT insulator nor the Mott-Hubbard insulator in the Zaanen, Sawatzky, Allen scheme.

Author keywords:

ATOMIC SCREENING CONSTANTS; OPTICAL-CONDUCTIVITY; ELECTRONIC-STRUCTURE; PHASE-SEPARATION; SCF FUNCTIONS; SPECTRA; LAMNO3; LA1-XSRXMNO3; ANISOTROPY; ORTHOFERRITES

DOI:

10.1103/PhysRevB.82.035106

Web of Science ID:

ISI:000279687200001

Соавторы в МНС:

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Другие поля

Поле	Значение
Month	JUL 9
Publisher	AMER PHYSICAL SOC
Address	ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
Language	English
Article-Number	035106
EISSN	2469-9969
Keywords-Plus	ATOMIC SCREENING CONSTANTS; OPTICAL-CONDUCTIVITY; ELECTRONIC-STRUCTURE; PHASE-SEPARATION; SCF FUNCTIONS; SPECTRA; LAMNO3; LA1-XSRXMNO3; ANISOTROPY; ORTHOFERRITES
Research-Areas	Physics
Web-of-Science-Categories	Physics, Condensed Matter
ResearcherID-Numbers	Loshkareva, Natalia/K-1587-2013 Makhnev, Alexander/J-4842-2013 Nomerovannaya, Larisa/J-5601-2013
ORCID-Numbers	Loshkareva, Natalia/0000-0002-1701-8712 Makhnev, Alexander/0000-0003-2868-6713 Nomerovannaya, Larisa/0000-0001-7420-3511
Funding-Acknowledgement	RFBR {[}08-02-00633, 10-02-96032]; DPS program ``Physics of new materials and structures{''}
Funding-Text	We thank R. V. Pisarev for fruitful discussions. The present work was partly supported by the RFBR under Grants No. 08-02-00633 and No. 10-02-96032 (A.S.M.), the DPS program ``Physics of new materials and structures{''} (N.N.L)
Number-of-Cited-References	58
Usage-Count-Last-180-days	3
Usage-Count-Since-2013	43
Journal-ISO	Phys. Rev. B
Doc-Delivery-Number	622TA