Abstract : The charge density wave (CDW) can be strained by applied voltage or by charge transfer at junctions, or by an electric field which can also put the CDW into sliding. Such strains can give rise to local or long-range modulational instabilities. We consider and perform a numerical modeling for two cases of strained CDW, the case of voltage is applied along and across conducting chains. We consider the effect of random and periodic dislocation array on the X-ray profile and present the plausible scenario of a very long-wave coherent periodic unharmonic superstructure. For the voltage allied across the chains, we confirm the reconstruction of the junction by creating an array of dislocations, whose number increases by steps with increasing voltage. The dislocation cores concentrate most of the voltage drop across the junction, giving rise to an effective tunneling. We compare the results with the experiments on coherent micro-diffraction in blue bronzes and with tunneling experiments in NbSe3 and TaS3.
N. Kirova 1 A. Rojo-Bravo 2 S. Brazovskii 2
1 LPS – Laboratoire de Physique des Solides
2 LPTMS – Laboratoire de Physique Théorique et Modèles Statistiques
