Experimental observation of structural crossover in binary mixtures of colloidal hard spheres.

Journal article

Using confocal microscopy, we investigate the structure of binary mixtures of colloidal hard spheres with size ratio q=0.61. As a function of the packing fraction of the two particle species, we observe a marked change of the dominant wavelength in the pair-correlation function. This behavior is in excellent agreement with a recently predicted structural crossover in such mixtures. In addition, the repercussions of structural crossover on the real-space structure of a binary fluid are analyzed. We suggest a relation between crossover and the lateral extension of networks containing only equally-sized particles that are connected by nearest-neighbor bonds. This is supported by Monte Carlo simulations which are performed at different packing fractions and size ratios.

Authors: Baumgartl, J; Dullens, R; Dijkstra, M; Roth, R; Bechinger, C

• Publication status: Published
• Journal: Physical Review Letters
• Volume: 98
• Issue: 19
• Pages: 198303
• Publication date: 2007-05-01
• DOI: 10.1103/physrevlett.98.198303
• EISSN: 1079-7114
• ISSN: 0031-9007
• Language: English
• Keywords: cond-mat.soft; cond-mat.dis-nn