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Spin dynamics in the low-dimensional magnet TiOCl

D. V. Zakharov·J. Deisenhofer·H. -A. Krug von Nidda·P. Lunkenheimer·J. Hemberger·M. Hoinkis·M. Klemm·M. Sing·R. Claessen·M. V. Eremin·S. Horn·A. Loidl
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Abstract

We present detailed ESR investigations on single crystals of the low-dimensional quantum magnet TiOCl. The anisotropy of the g-factor indicates a stable orbital configuration below room temperature, and allows to estimate the energy of the first excited state as 0.3(1) eV ruling out a possible degeneracy of the orbital ground state. Moreover, we discuss the possible spin relaxation mechanisms in TiOCl and analyze the angular and temperature dependence of the linewidth up to 250 K in terms of anisotropic exchange interactions. Towards higher temperatures an exponential increase of the linewidth is observed, indicating an additional relaxation mechanism.

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D. V. Zakharov, J. Deisenhofer, H. -A. Krug von Nidda, P. Lunkenheimer, J. Hemberger, M. Hoinkis, M. Klemm, M. Sing, R. Claessen, M. V. Eremin, S. Horn, A. Loidl. 2006-02-28. Spin dynamics in the low-dimensional magnet TiOCl. https://doi.org/10.1103/physrevb.73.094452

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