Related papers: Effects of "stuffing" on the atomic and electronic…
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,…
Synthesis and crystal structures are described for the compounds Ln2(Ti2-xLnx)O7-x/2, where Ln = Tb, Dy, Ho, Er, Tm, Yb, Lu, and x ranges from 0 to 0.67. Rietveld refinements on X-ray powder diffraction data indicate that in Tb and Dy…
Pyrochlore systems are ideally suited to the exploration of geometrical frustration in three dimensions, and their rich phenomenology encompasses topological order and fractional excitations. Classical spin ices provide the first context in…
The very nature of the ground state of the pyrochlore compound Yb$_2$Ti$_2$O$_7$ is much debated, as experimental results demonstrate evidence for both a disordered or a long-range ordered ground state. Indeed, the delicate balance of…
The pyrochlore magnet $\rm Yb_2Ti_2O_7$ has been proposed as a quantum spin ice candidate, a spin liquid state expected to display emergent quantum electrodynamics with gauge photons among its elementary excitations. However, $\rm…
The interplay of spin-orbit interactions and electronic correlations dominates the physical properties of pyrochlore iridates, R2Ir2O7 (R = Y, rare earth element), which are typically magnetic insulators. We report an…
We report a structural and thermodynamic study of the "stuffed spin ice" material Ho2TiO5 (i.e., Ho2(Ti1.33Ho0.67)O6.67), comparing samples synthesized through two different routes. Neutron powder diffraction and electron diffraction reveal…
Extensive experimental investigations of the magnetic structures and excitations in the XY pyrochlores have been carried out over the last decade. Three families of XY pyrochlores have emerged: Yb$_2B_2$O$_7$, Er$_2B_2$O$_7$, and, most…
Time-of-flight neutron spectroscopy has been used to determine the crystalline electric field (CEF) Hamiltonian, eigenvalues and eigenvectors appropriate to the $J$ = 7/2 Yb$^{3+}$ ion in the candidate quantum spin ice pyrochlore magnet…
Elastic neutron scattering, ac susceptibility, and specific heat experiments on the pyrochlores Er$_{2}$Ge$_{2}$O$_{7}$ and Yb$_{2}$Ge$_{2}$O$_{7}$ show that both systems are antiferromagnetically ordered in the $\Gamma_5$ manifold. The…
The search for new quantum phases, especially in frustrated magnets, is central to modern condensed matter physics. One of the most promising places to look is in rare-earth pyrochlore magnets with highly-anisotropic exchange interactions,…
The charge ordered structure of ions and vacancies characterizing rare-earth pyrochlore oxides serves as a model for the study of geometrically frustrated magnetism. The organization of magnetic ions into networks of corner-sharing…
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…
A quantum spin liquid is a novel state of matter characterized by quantum entanglement and the absence of any broken symmetry. In condensed matter, the frustrated rare-earth pyrochlore magnets Ho$_2$Ti$_2$O$_7$ and Dy$_2$Ti$_2$O$_7$,…
Using density functional theory and LDA+U method, we investigate magnetic and electronic structure of Y$_{2}$Ir$_{2}$O$_{7}$ and rare-earth based pyrochlore iridates. Our study reveals that the ground state is a non-collinear magnetic…
If magnetic frustration is most commonly known for undermining long-range order, as famously illustrated by spin liquids, the ability of matter to develop new collective mechanisms in order to fight frustration is no less fascinating,…
We report inelastic neutron scattering measurements from our newly synthesized single crystals of the structurally metastable antiferromagnetic pyrochlore Yb$_{2}$Ge$_{2}$O$_{7}$. We determine the four symmetry-allowed nearest-neighbor…
There are two discrepant experimental results on the magnetic ground state of Y$_{2}$Mn$_{2}$O$_{7}$, one study proposes a spin glass state, while another introduces the material as a ferromagnet. In this study, we attempt to resolve this…
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…
We report low temperature specific heat and muon spin relaxation/rotation ($\mu$SR) measurements on both polycrystalline and single crystal samples of the pyrochlore magnet Yb$_2$Ti$_2$O$_7$. This system is believed to possess a spin…