相关论文: Frustrated Ferroelectricity in Niobate Pyrochlores

Polycrystalline Nd2Ru2O7 samples have been prepared and examined using a combination of structural, magnetic, and electrical and thermal transport studies. Analysis of synchrotron X-ray and neutron diffraction patterns suggests some site…

Recent neutron scattering and specific heat studies on the pyrochlore Yb2Ti2O7 have revealed variations in its magnetic behavior below 265mK. In the best samples, a sharp anomaly in the specific heat is observed at T=265mK. Other samples,…

In RBaCo4O7 (R = Ca, Y and Rare earth) cobaltite family, only CaBaCo4O7 shows 3D long range ferrimagnetic and spin driven electric polarization properties. In the present study, we have investigated the structural, magnetic and electric…

We report synchrotron radiation diffraction and muon spin rotation (muSR) measurements on the frustrated pyrochlore magnet Tb2Ti2O7. The powder diffraction study of a crushed crystal fragment does not reveal any structural change down to 4…

The origin of magnetic frustration was stated and the ions whose shift is accompanied by emerging magnetic ordering and ferroelectricity in TbMn2O5 and BiMn2O5 were determined on the basis of calculation of magnetic coupling parameters by…

We report the crystal structures, magnetic and thermodynamic properties of two magnetically frustrated $A$'$A$"$M_2$F$_7$-type antiferromagnets, NaCdNi$_2$F$_7$ and NaCdMn$_2$F$_7$. While NaCdNi$_2$F$_7$ forms a stable pyrochlore structure…

We report on the spin structure of the pyrochlore iridate Nd$_2$Ir$_2$O$_7$ that could be directly determined by means of powder neutron diffraction. Our magnetic structure refinement unravels a so-called all-in/all-out magnetic structure…

We report the crystal growth, crystal structure and basic magnetic properties of a new cobalt-based pyrochlore, NaSrCo$_2$F$_7$. Na and Sr are completely disordered on the non-magnetic large atom A sites, while magnetic S=3/2 Co$^{2+}$…

Within the past 20 years or so, there has occurred an explosion of interest in the magnetic behavior of pyrochlore oxides of the type $A_{2}^{3+}$$B_{2}^{4+}$O$_{7}$ where $A$ is a rare-earth ion and $B$ is usually a transition metal. Both…

Neutron powder diffraction and inelastic measurements were performed examining the 5d pyrochlore Y$_2$Ir$_2$O$_7$. Temperature dependent measurements were performed between 3.4 K and 290 K, spanning the magnetic transition at 155 K. No sign…

We have studied the frustrated system YBaCo4O7 generally described as an alternating stacking of Kagome and triangular layers of magnetic ions on a trigonal lattice, by single crystal neutron diffraction experiments above the Neel ordering…

We report the ferroelectric property in Tb2Ti2O7 pyrochlore, prepared by a two-step solid-state reaction method. A concave P-E (polarisation vs electric field) loop observed from 382 K confirms ferroelectricity, below which the loop remains…

A new charge-ordered magnetically frustrated mixed-metal fluoride with a pyrochlore-related structure has been synthesized and characterized. The material, RbFe2F6 (RbFe2+Fe3+F6) was synthesized through mild hydrothermal conditions. The…

Effects of Fe-substitution on the crystal structure and magnetic correlations of the geometrically frustrated antiferromagnets YBaCo4-xFexO7+{\delta} (x = 0, 0.2, 0.4, 0.5, 0.6, and 0.8) have been studied by neutron diffraction, M\"ossbauer…

The consequences of nonmagnetic-ion dilution for the pyrochlore family Y$_{2}$($M_{1-x}N_{x}$)$_{2}$O$_{7}$ ($M$ = magnetic ion, $N$ = nonmagnetic ion) have been investigated. As a first step, we experimentally examine the magnetic…

CoAl2O4 spinel with magnetic Co2+ ions on the diamond A-lattice is known to be magnetically frustrated. We compare neutron single crystal diffraction patterns measured in zero and applied magnetic fields with the ones obtained from…

We report the growth of large high quality crystals of the frustrated magnet, Pr2Zr2O7 by the floating zone technique. Several crystals have been produced starting with varying levels of excess of Pr6O11 to compensate for the loss of Pr2O3…

Geometrical frustration, as in pyrochlore lattices made of corner-sharing tetrahedra, precludes the onset of conventional magnetic ordering, enabling the stabilization of fluctuating spin states at low temperature. Disorder is a subtle…

The Ho2Ti2O7, Er2Ti2O7 and Yb2Ti2O7 pyrochlores were studied by synchrotron X-ray diffraction to determine whether the (002) peak, forbidden in the pyrochlore space group Fd-3m but observed in single crystal neutron scattering measurements,…

In this review we provide an introduction to the physics of a series of frustrated quantum rare-earth pyrochlores. We first give a background on the microscopic single- and two-ion physics of these materials, discussing the origins and…