49 citations · 375 across the 15 of their papers we have counts for
15 papers
Sodium layer chiral distribution and spin structure of NaNiTeO with a honeycomb network
Sunil K. Karna, Y. Zhao, R. Sankar +7
The nature of Na ion distribution, diffusion path, and the spin structure of -type NaNiTeO with a Ni honeycomb network has been explored. The nuclear density distri…
SR study of noncentrosymmetric superconductor PbTaSe
M. N. Wilson, A. M. Hallas, Y. Cai +6
We present muon spin rotation (SR) measurements on the noncentrosymmetric superconductor PbTaSe. From measurements in an applied transverse field between and $H_{c2…
Quasiparticle-continuum level repulsion in a quantum magnet
K. W. Plumb, Kyusung Hwang, Y. Qiu +7
When the energy eigenvalues of two coupled quantum states approach each other in a certain parameter space, their energy levels repel each other and level crossing is avoided. Such…
pi-bonds in graphene and surface of topological insulator Bi2Se3
G. J. Shu, S. C. Liou, F. C. Chou
Chemical bond analysis for the topological insulator (TI) Bi2Se3 following valence bond theory and VSEPR rule is proposed and compared to that of graphene. The existence of pi-bond…
PbCu3TeO7: An S=1/2 staircase Kagome lattice with significant intra- and inter-plane couplings
B. Koteswararao, R. Kumar, Jayita Chakraborty +5
We have synthesized polycrystalline and single crystal samples of PbCu3TeO7 and studied its properties via magnetic susceptibility chi(T) and heat-capacity Cp(T) measurements and a…
Anomalous behavior in the phonon dispersion of the (001) surface of BiTe determined from helium atom-surface scattering measurements
Colin Howard, M. El-Batanouny, R. Sankar +1
We employ inelastic helium atom-surface scattering to measure the low energy phonon dispersion along high-symmetry directions on the surface of the topological insulator BiTe$_…
Evidence for Dimer Crystal Melting in the Frustrated Spin-Ladder BiCu2PO6
K. -Y. Choi, J. W. Hwang, P. Lemmens +3
In the spin ladder compound BiCuPO there exists a decisive dynamics of spin excitations that we classify and characterize using inelastic light scattering. We observe low-e…
Plasmons dispersion and nonvertical interband transitions in single-crystal Bi2Se3 investigated by electron energy loss spectroscopy
S. C. Liou, M. -W. Chu, R. Sankar +4
Plasmons dispersion and nonvertical interband transitions in Bi2Se3 single crystals were investigated by electron energy-loss spectroscopy in conjunction with (scanning) transmissi…
Absence of static magnetic order in lightly-doped Ti1-xScxOCl down to 1.7 K
A. A. Aczel, G. J. MacDougall, F. L. Ning +5
Impurity-induced magnetic order has been observed in many quasi-1D systems including doped variants of the spin-Peierls system CuGeO3. TiOCl is another quasi-1D quantum magnet with…
Nonmagnetic impurity perturbation to the quasi-two-dimensional quantum helimagnet LiCu2O2
H. C. Hsu, J. -Y. Lin, W. L. Lee +6
A complete phase diagram of Zn substituted quantum quasi-two-dimensional helimagnet LiCu2O2 has been presented. Helical ordering transition temperature (T_h) of the original LiCu2O…
Suppression of the commensurate spin-Peierls state in Sc-doped TiOCl
J. P. Clancy, B. D. Gaulin, J. P. Castellan +2
We have performed x-ray scattering measurements on single crystals of the doped spin-Peierls compound Ti(1-x)Sc(x)OCl (x = 0, 0.01, 0.03). These measurements reveal that the presen…
Anomalous electronic Raman scattering in Na_xCoO_2 H_2O
P. Lemmens, K. Y. Choi, V. Gnezdilov +5
Raman scattering experiments on Na_{x}CoO_2 yH_2O single crystals show a broad electronic continuum with a pronounced peak around 100 cm-1 and a cutoff at approximately 560 cm-1ove…
Spin gap formation in the quantum spin systems TiOX, X=Cl and Br
P. Lemmens, K. Y. Choi, R. Valenti +4
In the layered quantum spin systems TiOCl and TiOBr the magnetic susceptibility shows a very weak temperature dependence at high temperatures and transition-induced phenomena at lo…
Giant phonon anomalies in the pseudo-gap phase of TiOCl
P. Lemmens, K. Y. Choi, G. Caimi +4
We report infrared and Raman spectroscopy results of the spin-1/2 quantum magnet TiOCl. Giant anomalies are found in the temperature dependence of the phonon spectrum, which hint t…
63Cu NQR evidence of dimensional crossover to anisotropic 2d regime in S= 1/2 three-leg ladder Sr2Cu3O5
K. R. Thurber, T. Imai, T. Saitoh +3
We probed spin-spin correlations up to 725 K with 63Cu NQR in the S= 1/2 three-leg ladder Sr2Cu3O5. We present experimental evidence that below 300 K, weak inter-ladder coupling ca…