Luke J. Sandilands

Scattering continuum and possible fractionalized excitations in α-RuCl(3).

The combination of electronic correlation and spin-orbit coupling is thought to precipitate a variety of highly unusual electronic phases in solids, including topological and quantum spin liquid states. We report a Raman scattering study that provides evidence for unconventional excitations in α-RuCl_{3}, a spin-orbit coupled Mott insulator on the honeycomb lattice. In particular, our measurements reveal unusual magnetic scattering, typified by a broad continuum. The temperature dependence of this continuum is evident over a large scale compared to the magnetic ordering temperature, suggestive of frustrated magnetic interactions. This is confirmed through an analysis of the phonon linewidths, which show a related anomaly due to spin-phonon coupling. These observations are in line with theoretical expectations for the Heisenberg-Kitaev model and suggest that α-RuCl_{3} may be close to a quantum spin liquid ground state.

Spin-orbit excitations and electronic structure of the putative Kitaev magnetα−RuCl3

Mott insulators with strong spin-orbit coupling have been proposed to host unconventional magnetic states, including the Kitaev quantum spin liquid. The

Optical Spectroscopic Studies of the Metal-Insulator Transition Driven by All-In-All-Out Magnetic Ordering in 5d Pyrochlore Cd(2)Os(2)O(7).

4d

Two-magnon scattering in the 5d all-in-all-out pyrochlore magnet Cd2Os2O7

system

Strong Spin-Phonon Coupling Mediated by Single Ion Anisotropy in the All-In–All-Out Pyrochlore Magnet Cd2Os2O7

ensuremath{alpha}ensuremath{-}{mathrm{RuCl}}_{3}

X-ray Absorption Spectroscopy Study of the Effect of Rh doping in Sr2IrO4

has recently come into view as a candidate Kitaev system, with evidence for unusual spin excitations in magnetic scattering experiments. We apply a combination of optical spectroscopy and Raman scattering to study the electronic structure of this material. Our measurements reveal a series of orbital excitations involving localized total angular momentum states of the Ru ion, implying that strong spin-orbit coupling and electron-electron interactions coexist in this material. Analysis of these features allows us to estimate the spin-orbit coupling strength, as well as other parameters describing the local electronic structure, revealing a well-defined hierarchy of energy scales within the Ru

Doping-dependent charge dynamics inCuxBi2Se3

d

Spin-Orbit Coupling and Interband Transitions in the Optical Conductivity of Sr2RhO4

states. By comparing our experimental results with density functional theory calculations, we also clarify the overall features of the optical response. Our results demonstrate that

Author Correction: Two-magnon scattering in the 5 d all-in-all-out pyrochlore magnet Cd 2 Os 2 O 7

ensuremath{alpha}ensuremath{-}{mathrm{RuCl}}_{3}

Optical probe of Heisenberg-Kitaev magnetism in .ALPHA.-RuCl3

is an ideal material system to study spin-orbit coupled magnetism on the honeycomb lattice.