Evolution of disordered hyperuniformity in block copolymers thin films by homopolymer dilution

Disordered hyperuniform materials display long range order despite their seemingly random structure – long range density fluctuations are suppressed as reflected in a vanishing structure factor at zero wavevector. Close-packed micelles of block copolymers (BCPs) display such behavior. Here, we explore the degree of structural order in BCP thin films and manipulation of such order, through the lens of disordered hyperuniformity. We explore the effect of gradually increasing disorder by increasing the nearest-neighbor distance between micelles by homopolymer addition. The hyperuniformity of the system is evaluated as a function of BCP concentration via numerical image analysis of AFM or SEM images of the BCP films. We observe a continuous transition from a DH state to randomly disordered, as characterized by the change in scaling of particle number density with increasing BCP dilution. These results offer a new perspective on structural order in BCP thin films and add to the understanding of the evolution and emergence of hyperuniform states in disordered materials. The findings are also relevant for improved engineering of nanoscale arrays based on BCP templates towards ‘designer made’ DH materials.