THERMAL-CONDUCTIVITY OF THE SPIN-PEIERLS COMPOUND CUGEO3

The thermal conductivity of the pure and zinc-doped spin-Peierls compo und CuGeO3 is investigated for the first time. Characteristic features reflecting the changes in the phonon spectrum of the crystals are obs erved in the k(T) curves at a transition into the dimerized state in C uGeO3 at T-sp = 14.2 K and in Cu0.98Zn0.02GeO3 at T-sp = 10.6 K. Near the spin-Peierls transition temperature T-sp the thermal conductivity of Cu0.98Zn0.02GeO3 (k=3 W/m.K) is much less than the thermal conducti vity of CuGeO3 (k=21.5 W/m.K). (C) 1997 American Institute of Physics. [S0021-3640(97)01424-2].