Related papers: Metal-insulator transitions in pyrochlore oxides
We highlight recent advances in the theory, materials fabrication, and experimental characterization of strongly correlated and topological states in [111] oriented transition metal oxide thin films and heterostructures, which are…
Evidence for another phase transition at 120 K in the metallic pyrochlore oxide Cd2Re2O7, following the structural transition at 200 K and followed by the superconducting transition at 1.0 K, is given through resistivity, magnetoresistance,…
The crystal structures of the A2B2O7-x Niobium-based pyrochlores Y2(Nb0.86Y0.14)2O6.91, CaYNb2O7, and Y2NbTiO7 are reported, determined by powder neutron diffraction. These compounds represent the first observation of B-site displacements…
We report on the study of unusual spin glass properties in the geometrically frustrated pyrochlore Tb$_{2}$Mo$_{2}$O$_{7}$, $T$$_{g}$$\simeq$24 K. The analysis of the nonlinear part of dc and complex susceptibilities, near the glass…
We present a theory of the metal-insulator transition in a disordered two-dimensional electron gas. A quantum critical point, separating the metallic phase which is stabilized by electronic interactions, from the insulating phase where…
Motivated by experiments on Pr2Ir2O7, we consider metallic pyrochlore systems A2B2O7, where the A-sites are occupied by rare-earth local moments and the B-sites host 5d transition metal ions with itinerant strongly spin-orbit coupled…
We discuss phenomena arising from the combined influence of electron correlation and spin-orbit coupling, with an emphasis on emergent quantum phases and transitions in heavy transition metal compounds with 4d and 5d elements. A common…
Transition-metal oxides have been a central subject of condensed matter physics for decades. In addition to novel electronic states driven by the influence of strong correlation, relativistic spin-orbit coupling effects have recently…
A2Ir2O7 iridates were proven to crystallise in the geometrically frustrated pyrochlore structure, which remains stable upon rare-earth cation substitution, temperature variation, and external pressure application. However, the change of…
In this review, I present the electronic properties of the beta-pyrochlore oxide CsW2O6 and other related materials. At 215 K, CsW2O6 exhibits an electronic phase transition to a nonmagnetic insulating state, which exhibits a complex…
We study theoretically the electronic states in a $5d$ transition metal oxide Na$_2$IrO$_3$, in which both the spin-orbit interaction and the electron correlation play crucial roles. Tight-binding model analysis together with the…
In transition-metal compounds, the transition-metal d electrons play an important role in their physical properties; however, the effects of the electron correlation between the ligand p electrons have not been clear yet. In this Letter,…
Optical conductivity spectra of cubic pyrochlore $Y_{2-x} Bi_x Ru_2 O_7$ (0.0$\leq ${\it x}$\leq $2.0) compounds are investigated. As a metal-insulator transition (MIT) occurs around {\it x}$=$0.8, large spectral changes are observed. With…
In frustrated magnetic systems, geometric constraints or the competition amongst interactions introduce extremely high degeneracy and prevent the system from readily selecting a low-temperature ground state. The most frustrated known spin…
The very low temperature properties of two pyrochlore compounds, Yb2Ti2O7 and Gd2Sn2O7, were investigated using an ensemble of microscopic and bulk techniques. In both compounds, a first order transition is evidenced, as well as spin…
In this overview we provide a general introduction to metal-insulator transitions, with focus on specific mechanisms that can localize the electrons in absence of magnetic or charge ordering, and produce well defined quantum critical…
The magnetic pyrochlore oxide materials of general chemical formula R2Ti2O7 and R2Sn2O7 (R = rare earth) display a host of interesting physical behaviours depending on the flavour of rare earth ion. These properties depend on the value of…
Entanglement underpins quantum information processing and computing, yet its experimental quantification in complex, many-body condensed matter systems remains a considerable challenge. Here, we reveal a highly entangled electronic phase…
We report on the evolution of the thermal metal-insulator transition in polycrystalline samples of Nd$_2$Ir$_2$O$_7$ upon hole-doping via substitution of Ca$^{2+}$ for Nd$^{3+}$. Ca substitution mediates a filling-controlled Mott-like…
The rich physics manifested by 5d oxides falls outside the Mott-Hubbard paradigm used to successfully explain the electronic and magnetic properties of 3d oxides. Much consideration has been given to the extent to which strong spin-orbit…