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arXiv · 1009.4185

Singlet-Triplet Excitations in the Unconventional Spin-Peierls System TiOBr

J. P. Clancy·B. D. Gaulin·C. P. Adams·G. E. Granroth·A. I. Kolesnikov·T. E. Sherline·F. C. Chou
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Abstract

We have performed time-of-flight neutron scattering measurements on powder samples of the unconventional spin-Peierls compound TiOBr using the fine-resolution Fermi chopper spectrometer (SEQUOIA) at the SNS. These measurements reveal two branches of magnetic excitations within the commensurate and incommensurate spin-Peierls phases, which we associate with n = 1 and n = 2 triplet excitations out of the singlet ground state. These measurements represent the first direct measure of the singlet-triplet energy gap in TiOBr, which is determined to be Eg = 21.2 +/- 1.0 meV.

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J. P. Clancy, B. D. Gaulin, C. P. Adams, G. E. Granroth, A. I. Kolesnikov, T. E. Sherline, F. C. Chou. 2010-09-21. Singlet-Triplet Excitations in the Unconventional Spin-Peierls System TiOBr. https://doi.org/10.1103/physrevlett.106.117401

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