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A system of strongly-interacting electron-lattice polarons can exhibit charge and orbital order at sufficiently high polaron concentrations. In this study, the structure of short-range polaron correlations in the layered colossal…

We present a simple model to study the electron doped manganese perovskites. The model considers the competition between double exchange mechanism for itinerant electrons and antiferromagnetic superexchange interaction for localized…

Condensed Matter · Physics 2016-08-31 H. Aliaga , R. Allub , B. Alascio

The short range ordered magnetic correlations have been studied in half doped La0.5Ca0.5-xSrxMnO3 (x = 0.1, 0.3 and 0.4) compounds by polarized neutron scattering technique. On doping Sr2+ for Ca2+ ion, these compounds with x = 0.1, 0.3,…

Materials Science · Physics 2015-05-18 I. Dhiman , A. Das , R. Mittal , Y. Su , A. Kumar , A. Radulescu

Manganites exhibit various types of electronic phenomena, and these electronic characteristics can be controlled by carrier doping. Herein, we report the dielectric and magnetic properties of electron-doped manganite…

A thin Hafnium film is shown to act both as an effective diffusion barrier for manganese at a thickness of 0.7 nm, and as an effective exchange coupling layer in a sandwich structure with perpendicular magnetic anisotropy. The magnetic…

Materials Science · Physics 2017-10-11 Kiril Borisov , Gwenaël Atcheson , Gavin D'Arcy , Yong-Chang Lau , J. M. D. Coey , Karsten Rode

The magnon exchange mechanism of superconductivity was developed to explain in a natural way the fact that the superconductivity in $UGe_2$, $ZrZn_2$ and $URhGe$ is confined to the ferromagnetic phase.The order parameter is a spin…

Superconductivity · Physics 2007-05-23 N. I. Karchev

We solve for the finite temperature collective mode dynamics in the Holstein-double exchange problem, using coupled Langevin equations for the phonon and spin variables. We present results in a strongly anharmonic regime, close to a…

Strongly Correlated Electrons · Physics 2020-03-30 Sauri Bhattacharyya , Sankha Subhra Bakshi , Saurabh Pradhan , Pinaki Majumdar

We report results of a Monte Carlo study of doped, diluted magnetic semiconductors in the low carrier density (insulating) regime. We find that the system undergoes a transition from a paramagnet at high temperatures to a ferromagnet at low…

Materials Science · Physics 2007-05-23 Xin Wan , R. N. Bhatt

We develop a variational mean-field theory of the ferromagnetic transition in compounds like Lanthanum-Manganite within the framework of the Double-Exchange Model supplemented by modest disorder. We obtain analytical expressions for the…

Materials Science · Physics 2021-05-26 E. E. Narimanov , C. M. Varma

We present a femtosecond optical pump-probe study of the multiferroic manganite Eu$_{0.75}$Y$_{0.25}$MnO$_3$. The optical response of the material at pump energies of 1.55 and 3.1 eV is dominated by the $d$-$d$ and $p$-$d$ transitions of…

We report Electron Paramagnetic Resonance measurements on single crystalline and powder samples of Nd_0.5Ca_0.5MnO_3 across the charge-ordering transition at T_co=240 K down to the antiferromagnetic ordering transition at T_N = 140 K. The…

Strongly Correlated Electrons · Physics 2021-05-26 Janhavi P. Joshi , Rajeev Gupta , A. K. Sood , S. V. Bhat , A. R. Raju , C. N. R. Rao

We present a hybrid quantum-classical simulation of charge-polaron transport in conjugated polymers. The charge, which couples to the angular rotations of the monomers, is modeled via the time-dependent Schr\"odinger equation, while the…

Statistical Mechanics · Physics 2022-01-11 Laszlo Berencei , William Barford , Stephen R. Clark

The effect of the exchange interaction on the vibrational properties and on the electron-phonon coupling were investigated in several recent works. In most of the case, exchange tends to enhance the electron-phonon interaction, although the…

Superconductivity · Physics 2018-03-14 Betul Pamuk , Paolo Zoccante , Jacopo Baima , Francesco Mauri , Matteo Calandra

Electrodynamic properties of La-doped SrTiO3 thin films with controlled elemental vacancies have been investigated using optical spectroscopy and thermopower measurement. In particular, we observed a correlation between the polaron…

Materials Science · Physics 2015-05-13 Woo Seok Choi , Hyang Keun Yoo , Hiromichi Ohta

An explanation is given for the charge order, orbital order and insulating state observed in half-doped manganese oxides, such as Nd$_{1/2}$Sr$_{1/2}$MnO$_{3}$. The competition between the kinetic energy of the electrons and the magnetic…

Strongly Correlated Electrons · Physics 2009-10-31 Jeroen van den Brink , Giniyat Khaliullin , Daniel Khomskii

Moir\'e heterostructures of transition metal dichalcogenides exhibit Mott-insulating behaviour both at half-filling as well as at fractional fillings, where electronic degrees of freedom form self-organized Wigner crystal states. An open…

Strongly Correlated Electrons · Physics 2024-01-31 Urban F. P. Seifert , Leon Balents

Transition metal oxides are a rich group of materials with very interesting physical properties that arise from the interplay of the charge, spin, orbital, and lattice degrees of freedom. One interesting consequence of this, encountered in…

Strongly Correlated Electrons · Physics 2019-09-11 Krzysztof Bieniasz , Mona Berciu , Andrzej M. Oleś

The interplay of magnetic excitations and itinerant charge carriers is a ubiquitous phenomenon in strongly correlated electron systems. In the vicinity of magnetically ordered phases, strong interactions between itinerant quasiparticles and…

We discuss magnetotransport in a low density electron gas coupled to spin fluctuations near and above a ferromagnetic transition. Provided the density is low enough ($n \lesssim 1/\xi^{3}(T)$, with $\xi(T)$ the ferromagnetic correlation…

Materials Science · Physics 2009-10-30 Pinaki Majumdar , Peter Littlewood

A detailed study of the electric field gradient (EFG) across the Pr1-xCaxMnO3 phase diagram and its temperature dependence is given. Clearly, distinct EFG behaviours for samples outside/inside the charge order (CO) region are observed. The…

Strongly Correlated Electrons · Physics 2009-11-13 A. M. L. Lopes , J. P. Araujo , V. S. Amaral , J. G. Correia , Y. Tomioka , Y. Tokura