Emergence of Long Range One-Dimensional Nanostructures in a Disordered Two-Dimensional System: Mn-Doped Ti1+δS2

Abstract

Multiple microscopic techniques have been employed to study Mn-intercalated Ti1+δS2 at different length scales. The introduction of Mn intercalates resulted in the formation of two distinct types of one-dimensional structures; both exhibited extremely high aspect ratios, with lengths exceeding hundreds of micrometers. The smaller of the two features were only a few nanometers wide, while the larger one-dimensional structures had widths on the order of magnitude of one hundred nanometers. The one-dimensional structures were detected on samples with a range of Mn-doping levels but were especially common in samples with a 15% Mn-doping concentration. In these samples, a high density of parallel linear structures could be found at lengths ranging from the nanometer to micrometer scale. One-dimensional structures were never found in Ti1+δS2 samples without Mn dopants. We utilized Monte Carlo simulations to better understand these structures, which arise from interactions between the two species of intercalates in the system: Mn ions and excess Ti ions bound to intercalation sites. While the arrangement of intercalated ions has no long-range order, interactions between various nanoscale domains leads to the formation of domain-wall-like structures extending over macroscopic distances.