Related papers: Reentrant charge ordering caused by polaron format…
The phenomenon of colossal magnetoresistance in manganites is generally agreed to be a result of competition between crystal phases with different electronic, magnetic, and structural order; a competition which can be strong enough to cause…
We theoretically explore the mechanism of the colossal magnetoresistance in manganese oxides by explicitly taking into account the phase competition between the double-exchange ferromagnetism and the charge-ordered insulator. We find that…
Resonant absorption of a photon by bound electrons in a solid can promote an electron to another orbital state or transfer it to a neighboring atomic site. Such a transition in a magnetically ordered material could affect the magnetic…
Understanding orbital ordered (OO) Mott insulating states lies at the heart of a consistent resolution of the colossal magneto-resistance (CMR) observed in manganites, where its melting induces a low-$T$ insulator-metal transition for $0.25…
A model of localized classical electrons coupled to lattice degrees of freedom and, via the Coulomb interaction, to each other, has been studied to gain insight into the charge and orbital ordering observed in lightly doped manganese…
We investigated the series of temperature and field-driven transitions in LuFe$_2$O$_4$ by optical and M\"{o}ssbauer spectroscopies, magnetization, and x-ray scattering in order to understand the interplay between charge, structure, and…
In order to clarify the mechanism associated with pressure/magnetic-field-induced giant ferroelectric polarization in TbMnO3, this work investigated changes in magnetic ordering brought about by variations in temperature, magnetic field,…
The transmission electron microscopy observations of the charge ordering (CO) which governs the electronic polarization in LuFe2O4-x clearly show the presence of a remarkable phase separation at low temperatures. Two CO ground states are…
The conventional paradigm of charge order for La_{1-x}Ca_xMnO_3 for x=0.5 has been challenged recently by a Zener polaron picture emerging from experiments and theoretical calculations. The effective low energy Hamiltonian for the magnetic…
Interesting emergent behavior in quantum materials arises when the interaction of electrons with the lattice leads to partial localization and ordering of charge at low temperatures. The triangular lattice of some transition metal…
Using the point contact Andreev reflection technique, we have carried out a systematic study of the spin polarization in the colossal magnetoresistive manganite, La$_{0.7}$Sr$_{0.3}$MnO$_{3}$} (LSMO). Surprisingly, we observed a significant…
The low temperature phase of single crystals of Nd$_{0.5}$Ca$_{0.5}$MnO$_3$ and Gd$_{0.5}$Ca$_{0.5}$MnO$_3$ manganites is investigated by squid magnetometry. Nd$_{0.5}$Ca$_{0.5}$MnO$_3$ undergoes a charge-ordering transition at…
The complete magnetic and multiferroic phase diagram of Mn$_{1-x}$Co$_{x}$WO$_4$ single crystals is investigated by means of magnetic, heat capacity, and polarization experiments. We show that the ferroelectric polarization…
The compound La1-xSrxMnO3 exhibits a charge order (CO) state at $x\approx 1/8$ and $T<T_{co}$, which recalls the CO state with a decrease in the temperature of the superconducting transition, $T_c$, observed in all cuprates at this doping…
Understanding the interplay between charge and spin and its effects on transport is a ubiquitous challenge in quantum many-body systems. In the Fermi-Hubbard model, this interplay is thought to give rise to magnetic polarons, whose dynamics…
The checkerboard lattice, with alternating 'crossed' plaquettes, serves as the two dimensional analog of the pyrochlore lattice. The corner sharing plaquette structure leads to a hugely degenerate ground state, and no magnetic order, for…
Using Co-L_(2,3) and O-K x-ray absorption spectroscopy, we reveal that the charge ordering in La_(1.5)Sr_(0.5)CoO4 involves high spin (S=3/2) Co^2+ and low spin (S=0) Co^3+ ions. This provides evidence for the spin blockade phenomenon as a…
We study theoretically low-temperature phases of a recently synthesized compound Sr$_2$CoO$_3$F under pressure. The analysis combining LDA+DMFT and a strong-coupling effective model points to the existence of not only normal paramagnetic…
Using ultrafast optical spectroscopy, we show that polaronic behavior associated with interfacial antiferromagnetic order is likely the origin of tunable magnetotransport upon switching the ferroelectric polarity in a…
The structure of bound magnetic polarons in an antiferromagnetic matrix is studied in the framework of two-dimensional (2D) and three-dimensional (3D) Kondo-lattice models in the double exchange limit (J_H >> t). The conduction electron is…