Interactions and correlations of particulate inclusions in a columnar phase

We calculate the elastic-field-mediated interaction between macroscopic particles in a columnar hexagonal phase. The interaction is found to be long-ranged and non-central, with both attractive and repulsive parts. We show how the interaction modifies the particle correlations and the column fluctuations. We also calculate the interaction of particles with the topological defects of the columnar phase. The particle-defect interaction reduces the mobility of the defects. Received 14 March 2002 and Received in final form 13 August 2002 RID="a" ID="a"e-mail: rjoy@physics.iisc.ernet.in