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Extremely Small Energy Gap in the Quasi-One-Dimensional Conducting Chain Compound SrNbO$_{3.41}$

C. A. Kuntscher·S. Schuppler·P. Haas·B. Gorshunov·M. Dressel·M. Grioni·F. Lichtenberg·A. Herrnberger·F. Mayr·J. Mannhart
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Abstract

Resistivity, optical, and angle-resolved photoemission experiments reveal unusual one-dimensional electronic properties of highly anisotropic SrNbO$_{3.41}$. Along the conducting chain direction we find an extremely small energy gap of only a few meV at the Fermi level. A discussion in terms of typical 1D instabilities (Peierls, Mott-Hubbard) shows that neither seems to provide a satisfactory explanation for the unique properties of SrNbO$_{3.41}$.

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C. A. Kuntscher, S. Schuppler, P. Haas, B. Gorshunov, M. Dressel, M. Grioni, F. Lichtenberg, A. Herrnberger, F. Mayr, J. Mannhart. 2003-01-15. Extremely Small Energy Gap in the Quasi-One-Dimensional Conducting Chain Compound SrNbO$_{3.41}$. https://doi.org/10.1103/physrevlett.89.236403

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