Charge density waves modulation in different chains of NbSe₃

Abstract

Using low temperature (LT) scanning tunnelling microscopy (STM) under ultra-high vacuum (UHV), we studied charge density waves (CDW) modulations in different chains of NbSe 3 at 5 K and 78 K. Both the underlying molecular lattice and two (one) CDW superlattice (s) were observed simultaneously at 5 K (78 K) with atomic resolution. Three types of chains were present in topographical constant current images showing different bias voltage dependence. Different from the early STM observation, at 5 K, the modulation of LT-CDW in chain I is found to be 2-3 times more important than that in chain II.