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Dopant-Bound Spinons in Cu_(1-x)Zn_xGeO_3

G. Els·G. S. Uhrig·P. Lemmens·H. Vonberg·P. H. M. van Loosdrecht·G. Guentherodt·O. Fujita·J. Akimitsu·G. Dhalenne·A. Revcolevschi
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Abstract

Polarized inelastic light scattering experiments on Cu_(1-x)Zn_xGeO_3 (0<= x <= 0.045) single crystals show for x<>0 a new distinct mode at nearly half the energy of the singlet response below the spin-Peierls transition. The temperature, magnetic field, polarization, and doping dependencies of this mode are similar to those of the singlet bound state. The data are interpreted in terms of a spinon-assisted light scattering process. Position and form of the peak provide strong evidence for the presence of dopant-bound spinons in Cu_(1-x)Zn_xGeO_3.

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G. Els, G. S. Uhrig, P. Lemmens, H. Vonberg, P. H. M. van Loosdrecht, G. Guentherodt, O. Fujita, J. Akimitsu, G. Dhalenne, A. Revcolevschi. 1998-08-06. Dopant-Bound Spinons in Cu_(1-x)Zn_xGeO_3. https://doi.org/10.1209/epl%2Fi1998-00382-3

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