Pini D, Lo Verso F, Tau M, Parola A, Reatto L
Dipartimento di Fisica, Università di Milano, Via Celoria 16, 20133 Milano, Italy.
Phys Rev Lett. 2008 Feb 8;100(5):055703. doi: 10.1103/PhysRevLett.100.055703.
We investigate critical phenomena in colloids by means of the renormalization-group based hierarchical reference theory of fluids. We focus on three experimentally relevant model systems: namely, the Asakura-Oosawa model of a colloidal dispersion under the influence of polymer-induced attractive depletion forces; fluids with competing short-range attractive and longer-range repulsive interactions; solutions of star polymers whose pair potential presents both an attractive well and an ultrasoft repulsion at shorter distance. Our results show that the ability to tune the effective interactions between colloidal particles allows one to generate a variety of crossovers to the asymptotic critical behavior, which are not observed in atomic fluids.
我们借助基于重整化群的流体层次参考理论来研究胶体中的临界现象。我们聚焦于三个与实验相关的模型系统：即，在聚合物诱导的吸引性耗尽力影响下的胶体分散体的朝仓-大泽模型；具有相互竞争的短程吸引和长程排斥相互作用的流体；其对势在较短距离呈现出一个吸引阱和超软排斥的星型聚合物溶液。我们的结果表明，调节胶体颗粒之间有效相互作用的能力使人们能够产生多种向渐近临界行为的转变，而这些转变在原子流体中并未观察到。
