相关论文: Orbital degree of freedom in high entropy oxides
The concept of spin-orbital entanglement on superexchange bonds in transition metal oxides is introduced and explained on several examples. It is shown that spin-orbital entanglement in superexchange models destabilizes the long-range (spin…
We present the main features of the spin-orbital superexchange which describes the magnetic and optical properties of Mott insulators with orbital degrees of freedom. In contrast to the SU(2) symmetry of spin superexchange, the orbital part…
A short introduction to the complex phenomena encountered in transition metal oxides with either charge or orbital or joint charge-and-orbital order, usually accompanied by magnetic order, is presented. It is argued that all the types of…
We report a thorough study of Y$_{0.7}$La$_{0.3}$VO$_3$ single crystals by measuring magnetic properties, specific heat, thermal conductivity, x-ray and neutron diffraction with the motivation of revealing the lattice response to the…
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…
The properties of Mott insulators with orbital degrees of freedom are described by spin-orbital superexchange models, which provide a theoretical framework for understanding their magnetic and optical properties. We introduce such a model…
Roles of orbital degree of freedom of Mn ions in phase transition as a function of temperature and hole concentration in perovskite manganites are studied. It is shown that the orbital order-disorder transition is of the first order in the…
Rich properties of systems with strongly correlated electrons, such as transition metal oxides, is largely connected with an interplay of different degrees of freedom in them: charge, spin, orbital ones, as well as crystal lattice. Specific…
We consider strongly spin-orbit coupled double perovskites A$_2$BB'O$_6$ with B' magnetic ions in either $d^1$ or $d^2$ electronic configuration and non-magnetic B ions. We provide insights into several experimental puzzles, such as the…
MgV$_{2}$O$_{4}$ is a spinel based on magnetic V$^{3+}$ ions which host both spin ($S=1$) and orbital ($l_{eff}=1$) moments. Owing to the underlying pyrochlore coordination of the magnetic sites, the spins in MgV$_{2}$O$_{4}$ only…
Transition metal oxides whose lattice structure has edge-sharing network of octahedra constitute a diverse group of intriguing materials besides compounds with corner-sharing octahedra such as perovskites. We present a theoretical…
We introduce a microscopic model which unravels the physical mechanisms responsible for the observed phase diagram of the $R$VO$_3$ perovskites. It reveals a nontrivial interplay between superexchange, the orbital-lattice coupling due to…
Spin-state ordering - a periodic pattern of ions with different spin-state configurations along a crystal lattice - is a rare phenomenon, and its possible interrelation with other electronic degrees of freedom remains little explored. Here…
Disorder can have a dominating influence on correlated and quantum materials leading to novel behaviors which have no clean limit counterparts. In magnetic systems, spin and exchange disorder can provide access to quantum criticality,…
We describe a variational theory of multi-band two-dimensional electron gases that captures the interplay between electrostatic confining potentials, orbital-dependent interlayer electronic hopping and electron-electron interactions, and…
Perovskite oxides ($AB$O$_3$) have long been central to the advancement of modern condensed matter physics, owing to their rich and tunable electronic and magnetic properties. The quest to understand their various entangled phases has…
Using the multi-band $d-p$ model and unrestricted Hartree-Fock approximation we investigate the electronic structure and spin-orbital order in three-dimensional VO$_3$ lattice. The main aim of this investigation is testing if simple $d-p$…
Hybrid organic-inorganic perovskites (HOIP) have emerged in recent years as highly promising semiconducting materials for a wide range of optoelectronic and energy applications. Nevertheless, the rotational dynamics of the organic…
Entropy is a critical, but often overlooked, factor in determining the relative stabilities of crystal phases. The importance of entropy is most pronounced in softer materials, where small changes in free energy can drive phase transitions,…
The spin and orbital phase diagram for perovskite manganites are investigated as a function of temperature and hole concentration. The superexchange and double exchange interactions dominate the ferromagnetic phases in the low and high…