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Soliton Lattices in the Incommensurate Spin-Peierls Phase: Local Distortions and Magnetizations

Goetz S. Uhrig·Friedhelm Schoenfeld·Jean-Paul Boucher·Mladen Horvatic
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Abstract

It is shown that nonadiabatic fluctuations of the soliton lattice in the spin-Peierls system CuGeO_3 lead to an important reduction of the NMR line widths. These fluctuations are the zero-point motion of the massless phasonic excitations. Furthermore, we show that the discrepancy of X-ray and NMR soliton widths can be understood as the difference between a distortive and a magnetic width. Their ratio is controlled by the frustration of the spin system. By this work, theoretical and experimental results can be reconciled in two important points.

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Goetz S. Uhrig, Friedhelm Schoenfeld, Jean-Paul Boucher, Mladen Horvatic. 1999-02-19. Soliton Lattices in the Incommensurate Spin-Peierls Phase: Local Distortions and Magnetizations. https://doi.org/10.1103/physrevb.60.9468

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