Localized Charge Density Wave Enhancement Induced by Domain Boundaries in Monolayer NbTe 2

Abstract The manipulation of charge density waves (CDWs) at the atomic scale offers a powerful approach to investigate their interplay with other quantum states. Monolayer NbTe 2 , which hosts coexisting 4×4 and 4×1 CDW phases, provides an ideal platform for such nanoscale exploration. Using scanning tunneling microscopy and spectroscopy (STM/S), we investigate the topography and electronic states of monolayer NbTe 2 near the boundaries between these CDW domains. We find a pronounced enhancement in both STM topography and the spectral weight of the valence band state (V 1 ) within the 4×4 CDW phase as its domain boundary is approached. This spatial evolution of topography and electronic states, accompanied by a downward band bending suggests a localized enhancement of the CDW order near the boundary. Based on the enhancement of the V 1 spectral weight, together with the large atomic spacing near the boundary, we suggest that a localized structural distortion may reinforce the CDW modulation and drive the accompanying electronic reconstruction. Our work highlights the critical role of nanoscale strain fields at structural interfaces in tailoring local electronic properties, offering a new dimension for understanding CDW phenomena in two-dimensional materials.