Related papers: Low-temperature specific-heat studies on two squar…
We determined the spin exchanges between the Cu2+ ions in the kagome layers of volborthite, Cu3V2O7(OH)2x2H2O, by performing the energy-mapping analysis based on DFT+U calculations, to find that the kagom\'e layers of Cu2+ ions are hardly…
We present the crystal structure and magnetic properties of Y$_{3}$Cu$_{9}$(OH)$_{19}$Cl$_{8}$, a stoichiometric frustrated quantum spin system with slightly distorted kagome layers. Single crystals of Y$_{3}$Cu$_{9}$(OH)$_{19}$Cl$_{8}$…
Over the last decade, the interest in the spin-$1/2$ Heisenberg antiferromagnet (HAF) on the square-kagome (also called shuriken) lattice has been growing as a model system of quantum magnetism with a quantum paramagnetic ground state,…
The hole-doped kagome lattice of Cu2+ ions in LaCuO2.66 was investigated by nuclear quadrupole resonance (NQR), electron spin resonance (ESR), electrical resistivity, bulk magnetization and specific heat measurements. For temperatures above…
Quantum spin liquids represent exotic states of spin systems characterized by long-range entanglement and emergent fractionalized quasiparticles. It is generally believed that disorder is hostile to quantum spin liquids. In our study, we…
We present thermodynamic studies of a new spin-1/2 antiferromagnet containing undistorted kagome lattices---barlowite Cu$_{4}$(OH)$_{6}$FBr. Magnetic susceptibility gives $\theta_{CW}$ = $-$136 K, while long-range order does not happen…
We synthesized single crystals of the new hexagonal compounds A$_2$Cu$_3$SnF$_{12}$ with A=Cs and Rb, and investigated their magnetic properties. These compounds are composed of Kagom\'{e} layers of corner-sharing CuF$_6$-octahedra.…
ScFe$_6$Ge$_4$ with the LiFe$_6$Ge$_4$-type structure (space group $R{\bar{3}}m$), which has a double-layered kagome lattice (18$h$ site) of Fe crystallographically equivalent to that of a well-known topological ferromagnet Fe$_3$Sn$_2$, is…
The distribution of chemically similar transition-metal ions is a fundamental issue in the study of herbertsmithite-type kagome antiferromagnets. Using synchrotron radiation, we have performed resonant powder x-ray diffractions on newly…
We present the hydrothermal synthesis, as well as structural and chemical analysis of single crystals on the compounds EuCu$_{3}$(OH)$_{6}$Cl$_{3}$, Zn$_{x}$Cu$_{4-x}$(OH)$_{6}$(NO$_{3}$)$_{2}$ and haydeeite, MgCu$_{3}$(OH)$_{6}$Cl$_{2}$…
We have investigated the ground state properties of the orthorhombic structure compound PrRu$_2$Ga$_8$ through electronic and magnetic properties studies. The compound crystallizes in the CaCo$_2$Al$_8$-type structure, belonging to space…
The structural and magnetic properties of the geometrically frustrated spin-$1/2$ capped-kagome antiferromagnet (RbCl)Cu$_{5}$P$_{2}$O$_{10}$ are investigated via temperature dependent x-ray diffraction, magnetization, heat capacity, and…
SrCuTe$_2$O$_6$ consists of a 3-dimensional arrangement of spin-$\frac{1}{2}$ Cu$^{2+}$ ions. The 1st, 2nd and 3rd neighbor interactions respectively couple Cu$^{2+}$ moments into a network of isolated triangles, a highly frustrated…
We report the specific heat of single crystals of the spin ice compound Dy$_2$Ti$_2$O$_7$ at temperatures down to 100 mK in the so-called Kagome ice state. In our previous paper, we showed the anisotropic release of residual entropy in…
We have systematically studied the magnetic properties of Cu$_{4-x}$Zn$_x$(OH)$_6$FBr by the neutron diffraction and muon spin rotation and relaxation ($\mu$SR) techniques. Neutron-diffraction measurements suggest that the long-range…
The emergent behavior of spin liquids that are born out of geometrical frustration makes them an intriguing state of matter. We show that in the quantum kagome antiferromagnet ZnCu$_3$(OH)$_6$SO$_4$ several different correlated, yet…
Thermodynamic and transport measurements on NaxCoO2 (x ~ 0.7-0.75) over a wide temperature range reveal a strongly enhanced low energy excitation spectrum. The zero-field specific heat and resistance at low temperature are proportional to…
Experimental studies of high-purity kagome-lattice antiferromagnets (KAFM) are of great importance in attempting to better understand the predicted enigmatic quantum spin-liquid ground state of the KAFM model. However, realizations of this…
We have carried out neutron powder-diffraction measurements on zinc paratacamite Zn$_x$Cu$_{4-x}$(OH)$_6$Cl$_2$ with $x=1$, and studied the heat capacity in fields of up to 9 T for $0.5 \leq x \leq 1$. The $x=1$ phase has recently been…
We report structural and magnetic properties of the spin-$\frac12$ quantum antiferromagnet Cu[C$_6$H$_2$(COO)$_4$][C$_2$H$_5$NH$_3$]$_2$ by means of single-crystal x-ray diffraction, magnetization, heat capacity, and electron spin resonance…