Phonon thermal conductivity of stripe ordering La2-xSrxNiO4

We have studied the thermal conductivity kappa of stripe ordering La2-xSrxNiO4. In particular, long range stripe order is well established for x = 1/3. For this composition re is enhanced in the charge ordering phase and exhibits a clear maximum at low T. Even small deviations from this stochiometry cause a strong change of kappa: the low T-maximum is suppressed and no anomaly is observed at high T. Our data confirm that the stripe phase is most stable for x = 1/3. Moreover, we find clear differences in the thermal conductivity for x > 1/3 and for x 1/3, respectively, which indicates different properties of the stripe ordered phase in these two regions of the phase diagram.