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Related papers: Microscopic examinations of Co valences and spin s…

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We have described properties of LiCoO_2 within the Quantum Atomistic Solid State (QUASST) theory taking into account very strong electron correlations, predominantly of the intra-atomic origin, spin-orbit coupling and the detailed local…

Strongly Correlated Electrons · Physics 2008-10-08 R. J. Radwanski , Z. Ropka

We present an inelastic neutron scattering study of the low energy crystal-field excitations in the lightly doped cobalt perovskite La_0.998Sr_0.002CoO_3. In contrast to the parent compound LaCoO_3 an inelastic peak at energy transfer ~0.75…

Strongly Correlated Electrons · Physics 2008-02-22 A. Podlesnyak , K. Conder , E. Pomjakushina , A. Mirmelstein , P. Allenspach , D. I. Khomskii

The electronic structure of epitaxial films on LaCoO3(LCO) has been studied within first principle electronic structure calculations. A spin state transition is found to take place as a function of lattice strain which freezes in the…

Strongly Correlated Electrons · Physics 2009-01-05 Kapil Gupta , Priya Mahadevan

The spin state transition in LaCoO$_3$ has eluded description for decades despite concerted theoretical and experimental effort. In this study, we approach this problem using fully charge self-consistent Density Functional Theory + Embedded…

Materials Science · Physics 2017-11-15 Bismayan Chakrabarti , Turan Birol , Kristjan Haule

The electronic structure and magnetic properties of a newly predicted stable ternary compound La$_{18}$Co$_{28}$Pb$_{3}$ are studied using electronic structure analysis. The ground state of this compound is ferromagnetic, with three…

Materials Science · Physics 2024-01-31 Weiyi Xia , Vladimir Antropov , Yongxin Yao , Cai-Zhuang Wang

Synchrotron X-ray powder diffraction experiments reveal that the transition from a magnetic intermediate spin (IS) state to a nonmagnetic low-spin (LS) ground state in LaCoO3 normally observed when cooling, manifests itself under pressure…

Materials Science · Physics 2009-11-07 T. Vogt , J. A. Hriljac , N. C. Hyatt , P. Woodward

We report on the observation of a strain-induced insulator state in ferromagnetic La_0.7Sr_0.3CoO_3 films. Tensile strain above 1% is found to enhance the resistivity by several orders of magnitude. Reversible strain of 0.15% applied using…

Strongly Correlated Electrons · Physics 2009-11-13 A. D. Rata , A. Herklotz , K. Nenkov , L. Schultz , K. Doerr

The rhodium doping in the LaCo$_{1-x}$Rh$_{x}$O$_3$ perovskite series ($x=0.02-0.5$) has been studied by X-ray diffraction, electric transport and magnetization measurements, complemented by electronic structure GGA+U calculations in…

Materials Science · Physics 2012-04-04 K. Knížek , J. Hejtmánek , M. Maryško , Z. Jirák , J. Buršík

We present powder and single crystal X-ray diffraction data as evidence for a monoclinic distortion in the low spin (S=0) and intermediate spin state (S=1) of LaCoO3. The alternation of short and long bonds in the ab plane indicates the…

Strongly Correlated Electrons · Physics 2009-11-10 G. Maris , Y. Ren , V. Volotchaev , C. Zobel , T. Lorenz , T. T. M. Palstra

The spin transition in LaCoO$_3$ has been investigated within the density-functional theory + dynamical mean-field theory formalism using continuous time quantum Monte Carlo. Calculations on the experimental rhombohedral atomic structure…

Strongly Correlated Electrons · Physics 2015-01-15 M. Karolak , M. Izquierdo , S. L. Molodtsov , A. I. Lichtenstein

We studied the spin-state responses to light impurity doping in low-spin perovskite LaCoO$_{3}$ (Co^3+: d^6) through magnetization and X-ray fluorescence measurements of single-crystal LaCo$_{0.99}$$M_{0.01}$O$_{3}$ ($M$ = Cr, Mn, Fe, Ni).…

Strongly Correlated Electrons · Physics 2014-07-17 Keisuke Tomiyasu , Yuuki Kubota , Saya Shimomura , Mitsugi Onodera , Hironori Nakao , Youichi Murakami

A heavy-mass electron state is realized in a doped valence bond solid (Ti1-xVx)2O3. In this system, itinerant holes mediate the mainly ferromagnetic RKKY interaction between the localized magnetic moments and become readily spin-polarized…

Strongly Correlated Electrons · Physics 2015-05-27 M. Uchida , Y. Onose , Y. Tokura

We have investigated electronic structures of a room temperature diluted magnetic semiconductor : Co-doped anatase $\rm TiO_{2}$. We have obtained the half-metallic ground state in the local-spin-density approximation(LSDA) but the…

Materials Science · Physics 2009-11-07 Min Sik Park , S. K. Kwon , B. I. Min

We investigate the detailed electronic structure of PrCoO$_3$ and its temperature evolution using state-of-the-art photoemission spectroscopy and ab initio band structure calculations. We observe that in addition to the correlation effect,…

Strongly Correlated Electrons · Physics 2009-11-13 S. K. Pandey , Swapnil Patil , V. R. R. Medicherla , R. S. Singh , Kalobaran Maiti

Epitaxial thin films of undoped LaCoO$_{3}$\@, of electron-doped La$_{0.7}$Ce$_{0.3}$CoO$_{3}$\@, and of hole-doped La$_{0.7}$Sr$_{0.3}$CoO$_{3}$\@ exhibit ferromagnetic order with a transition temperature $T_{\rm{C}}$ $\approx$ 85 K, 22 K,…

Strongly Correlated Electrons · Physics 2013-06-19 M. Merz , P. Nagel , C. Pinta , A. Samartsev , H. v. Loehneysen , M. Wissinger , S. Uebe , A. Assmann , D. Fuchs , S. Schuppler

We introduce and investigate an effective five-band model for $t_{2g}$ and $e_g$ electrons to describe doped cobalt oxides with Co$^{3+}$ and Co$^{4+}$ ions in two-dimensional CoO$_2$ triangular lattice layers, as in Na$_{1-x}$CoO$_2$. The…

Strongly Correlated Electrons · Physics 2013-08-06 Krzysztof Rościszewski , Andrzej M. Oleś

Optical absorption and transverse Kerr effect spectra, resistivity and magnetoresistance of La$_{1-x}$Sr$_{x}$CoO$_3$ ($x=0.15, 0.25, 0.35$) films have been studied. The temperature dependencies of the optical and magneto-optical properties…

In this contribution we derive and discuss energy levels of the strongly-correlated d2 configuration of the V3+ ion (LaVO3) and of d4 configuration of the Mn3+ ion (LaMnO3) in the octahedral surroundings in the presence of the spin-orbit…

Strongly Correlated Electrons · Physics 2007-05-23 R. J. Radwanski Z. Ropka

We investigate lattice dynamics in LaCoO$_3$ using inelastic neutron and x-ray scattering over $T = 2\mbox{-}650\,\mathrm{K}$, spanning the spin-state crossover at $T_{1} \approx 100\,\mathrm{K}$ and the insulator--metal transition at…

We study energetics and the nature of both homogeneous and mixed spin (MS) states in LaCoO$_3$ incorporating structural changes of the crystal volume expansion and the Co-O bond disproportionation (BD) during the spin-state transition using…

Strongly Correlated Electrons · Physics 2020-05-20 Hyowon Park , Ravindra Nanguneri , Anh T. Ngo