Reverse order-disorder transition of Janus particles confined in two dimensions.

Liang, Yihao; Ma, Boran; Olvera de la Cruz, Monica · Phys Rev E · 2021

basic_science · Level V

Where this comes from

Abstract

Janus particles with different patch sizes, confined to two dimensions, generate a series of patterns of interest to the field of nanoscience. Here we observe reverse melting, where for some densities the system melts under cooling. For a broad range of hydrophobic patch sizes (60^{∘}<θ_{0}<90^{∘}), a reentrant transition from solid to liquid and then to an ordered phase emerges as temperature (T) decreases due to the formation of rhombus chains at low T. This reentrant phase has pseudo long-range orientational order but short-range translational order, similar to a hexatic phase. Our work provides guidelines to study the melting and assembly of Janus particles in two dimensions, as well as mechanisms to generate phases with specific symmetry.