相关论文: Degenerate ground state in the classical pyrochlor…

Motivated by recent experiments on Na_4Ir_3O_8 [Y. Okamoto, M. Nohara, H. Aruga-Katori, and H. Takagi, arXiv:0705.2821 (unpublished)], we study the classical antiferromagnet on a frustrated three-dimensional lattice obtained by selectively…

The (three-dimensional) pyrochlore lattice antiferromagnet with Heisenberg spins of large spin length $S$ is a highly frustrated model with an macroscopic degeneracy of classical ground states. The zero-point energy of (harmonic order) spin…

Weak bond disorder disrupts the expected spin-liquid ground-state of the ideal $S$ = 1/2 Heisenberg pyrochlore antiferromagnet. Here we introduce a single crystal study of the structural and magnetic properties of the bond-disordered…

In the classical pyrochlore lattice Heisenberg antiferromagnet, there is a macroscopic continuous ground state degeneracy. We study semiclassical limit of large spin length $S$, keeping only the lowest order (in 1/S) correction to the…

The classical Heisenberg antiferromagnet on the pyrochlore lattice is macroscopically and continuously degenerate and the system remains disordered at all temperatures, even in the presence of weak dilution with nonmagnetic ions. We show…

We study spin correlations for the highly frustrated classical pyrochlore lattice antiferromagnets with O(N) symmetry in the limit T->0. We conjecture that a local constraint obeyed by the extensively degenerate ground states dictates a…

We study the low-temperature behaviour of the classical Heisenberg antiferromagnet with nearest neighbour interactions on the pyrochlore lattice. Because of geometrical frustration, the ground state of this model has an extensive number of…

We report low-temperature powder X-ray and neutron diffraction studies on breathing pyrochlore magnets Cu$M$Cr$_{4}$S$_{8}$ ($M$ = Al, Ga), which undergo a magnetic transition at $T_{\rm N} \approx$ 21 and 31 K for {$M$ = Al and Ga,…

In this study, I have investigated the magnetic and critical properties of manganese pyrochlore fluoride NaSrMn$_{2}$F$_{7}$, which exhibits a glass transition at T$_\text{f}$$=$2.5 (K) due to charge disorder. A DFT+$U$+SOC framework is…

The low temperature magnetic properties of pyrochlore compound Dy2Ti2O7 in magnetic fields applied along the [111] direction are reported. Below 1 K, a clear plateau has been observed in the magnetization process in the field range 2~9 kOe,…

Correlation functions (CFs) of the classical Heisenberg antiferromagnet on the pyrochlore lattice are studied by solving exactly the infinite-component spin-vector model. % As in many Fully Frustrated Lattices, the constraint due to the…

Thermal fluctuations lift the high ground state degeneracy of the classical nearest neighbour pyrochlore antiferromagnet, with easy plane anisotropy, giving a first order phase transition to a long range ordered state. We show, from spin…

The model 2d kagome system (H3O)Fe3(SO4)2(OH)6 and the 3d pyrochlore Y2Mo2O7 are two well characterized examples of low-disordered frustrated antiferromagnets which rather then condensing into spin liquid have been found to undergo a…

We discuss the ground state properties of a spin 1/2 magnetic ion with threefold $t_{2g}$ orbital degeneracy on a highly frustrated pyrochlore lattice, like Ti$^{3+}$ ion in B-spinel MgTi$_2$O$_4$. We formulate an effective spin-orbital…

The quantum pyrochlore antiferromagnet is studied by perturbative expansions and exact diagonalization of small clusters. We find that the ground state is a spin-liquid state: The spin-spin correlation functions decay exponentially with…

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$^{2+}$…

Motivated by puzzling spin-glass behaviors observed in many pyrochlore-based magnets, effects of magnetoelastic coupling to local lattice distortions were recently studied by the authors for a bond-disordered antiferromagnet on a pyrochlore…

Frustrated pyrochlore lattices in transition-metal oxides provide an ideal platform for realizing exotic quantum states, including spin liquids with unconventional low-energy excitations arising from the macroscopic ground-state degeneracy…

We report a random singlet ground state in the $S=\frac{1}{2}$ Heisenberg pyrochlore antiferromagnet NaCdCu$_2$F$_7$. Cationic Na$^+$/Cd$^{2+}$ disorder on the pyrochlore $A$ site generates a broad distribution of…

The three-dimensional frustrated spin lattice in MgCrGaO4, where Cr3+ ions occupy a pyrochlore-like network, exemplifies a quantum magnet with competing interactions, macroscopic degeneracy, and exotic low-energy excitations. Using…