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Solitary magnetic excitations in the low-carrier density, one-dimensional S=1/2 antiferromagnet Yb4As3.
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Köppen, Manfred and Pankert, D. and Hauptmann, and Lang, Michael and Weiden, and Geibel, Christoph and Steglich, Frank (1998):
Interference of a first-order transition with the formation of a spin-Peierls state in alpha'-NaV2O5.
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