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Unusual quasi-one-dimensional electron dispersions in the spin-1/2 quantum magnet TiOCl

M. Hoinkis·M. Sing·J. Schaefer·M. Klemm·S. Horn·H. Benthien·E. Jeckelmann·T. Saha-Dasgupta·L. Pisani·R. Valenti·R. Claessen
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Abstract

We have studied the electronic structure of the spin-1/2 quantum magnet TiOCl by polarization-dependent momentum-resolved photoelectron spectroscopy. From that, we confirm the quasi-one-dimensional nature of the electronic structure along the crystallographic b-axis and find no evidence for sizable phonon-induced orbital fluctuations as origin for the non-canonical phenomenology of the spin-Peierls transition in this compound. A comparison of the experimental data to our own LDA+U and Hubbard model calculations reveals a striking lack of understanding regarding the quasi-one-dimensional electron dispersions in the normal state of this compound.

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M. Hoinkis, M. Sing, J. Schaefer, M. Klemm, S. Horn, H. Benthien, E. Jeckelmann, T. Saha-Dasgupta, L. Pisani, R. Valenti, R. Claessen. 2005-07-29. Unusual quasi-one-dimensional electron dispersions in the spin-1/2 quantum magnet TiOCl. https://doi.org/10.1103/physrevb.72.125127

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