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arXiv · 0911.2573

Infrared optical absorption spectra of CuO single crystals: Fermion-spinon band and dimensional crossover of the antiferromagnetic order

SeongHoon Jung·Jooyeon Kim·E. J. Choi·Y. Sekio·T. Kimura·J. Lorenzana
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Abstract

We have obtained mid-infrared optical absorption spectra of the S=1/2 quasi one-dimensional CuO using polarized transmission measurement and interpreted the spectra in terms of phonon assisted magnetic excitations. When the electric field is parallel to the main antiferromagnetic direction a Delta shaped peak is observed with the maximum at 0.23eV which is attributed to spinons along Cu-O chains. At low temperatures in the antiferromagnetic phase another peak appears at 0.16eV which is attributed to two-magnon absorption but the spinon peak remains. This behavior is interpreted as due to a dimensional crossover where the low temperature three-dimensional magnetic phase keeps short range characteristics of a one-dimensional magnet.

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SeongHoon Jung, Jooyeon Kim, E. J. Choi, Y. Sekio, T. Kimura, J. Lorenzana. 2009-11-13. Infrared optical absorption spectra of CuO single crystals: Fermion-spinon band and dimensional crossover of the antiferromagnetic order. https://doi.org/10.1103/physrevb.80.140516

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