49 citations · 375 across the 15 of their papers we have counts for
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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…
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…
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…
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…