The Second Threshold Field of Charge-Density-Wave Conductor Rb_0.3MoO₃ in High Temperature Range

The switching and threshold properties of quasi-one-dimensional charge-density-wave conductor rubidium blue bronze Rb_0.33MoO₃ single crystals are investigated in a comparative high and large temperature range. Beyond the limit temperature 50K of Littlewood's theory, even up to about 100K, typical sharp switching to negative or zero differential resistance is observed in E-I characteristic curves. Correspondingly, an obvious switching between two conducting states, from a lowly conducting state to a highly conducting state, is observed in the I-E characteristic curves in the same temperature range. Temperature dependence of the second threshold field E_T2 accompanied by this kind of high field switching behaviour is firstly obtained. These new observations are discussed in the mechanism of the current inhomogeneity and redistribution due to the existence of transverse energy barriers suggested by Zhang et al. Solid State Commun. 85 (1993) 121