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arXiv · 1107.5800

Two-Spinon and Orbital Excitations of the Spin-Peierls System TiOCl

Sebastian Glawion·Jakoba Heidler·Maurits W. Haverkort·Laurent C. Duda·Thorsten Schmitt·Vladimir N. Strocov·Claude Monney·Kejin Zhou·Andreas Ruff·Michael Sing·Ralph Claessen
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Abstract

We combine high-resolution resonant inelastic x-ray scattering with cluster calculations utilizing a recently derived effective magnetic scattering operator to analyze the polarization, excitation energy, and momentum dependent excitation spectrum of the low-dimensional quantum magnet TiOCl in the range expected for orbital and magnetic excitations (0 - 2.5 eV). Ti 3d orbital excitations yield complete information on the temperature-dependent crystal-field splitting. In the spin-Peierls phase we observe a dispersive two-spinon excitation and estimate the inter- and intra-dimer magnetic exchange coupling from a comparison to cluster calculations.

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Sebastian Glawion, Jakoba Heidler, Maurits W. Haverkort, Laurent C. Duda, Thorsten Schmitt, Vladimir N. Strocov, Claude Monney, Kejin Zhou, Andreas Ruff, Michael Sing, Ralph Claessen. 2011-09-20. Two-Spinon and Orbital Excitations of the Spin-Peierls System TiOCl. https://doi.org/10.1103/physrevlett.107.107402

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