arXiv subjects

P. Bartlett

Publications and source records attributed to P. Bartlett.

2 recordsLinked to original sources

arXiv2000

Measurement of the hydrodynamic forces between two polymer-coated spheres

The hydrodynamic forces between Brownian spheres are determined from a measurement of the correlated thermal fluctuations in particle position using a new method, two-particle cross-correlation spectroscopy (TCS). A pair of 1.3 um diameter polymer-coated poly(methyl methacrylate) were held at separations of between 2 um and 20 um using optical traps. The mobility tensor is determined directly from the statistically-averaged Brownian fluctuations of the two spheres. The observed distance dependence of the mobility tensor is in quantitative agreement with low-Reynolds number calculations.

cond-mat.soft↗

arXiv1998

Fractionated crystallisation in a polydisperse mixture of hard spheres

We consider the nature of the fluid-solid phase transition in a polydisperse mixture of hard spheres. For a sufficiently polydisperse mixture crystallisation occurs with simultaneous fractionation. At the fluid-solid boundary, a broad fluid diameter distribution is split into a number of narrower fractions, each of which then crystallises. The number of crystalline phases increases with the overall level of polydispersity. At high densities, freezing is followed by a sequence of demixing transitions in the polydisperse crystal.

cond-mat↗