Capital equipment funds are provided for a dilution refrigerator and accessories. This equipment will be used on experiments which investigate the properties of two-dimensional fluids and solids supported by a liquid helium or solid hydrogen surface. This system, made up of simple particles with well understood interactions and supported by a smooth substrate, is a system easily subjected to theoretical analysis and is an ideal prototype of two-dimensional systems. Theory suggests that information gleaned from this system should be valuable in the understanding of phase transitions and other properties of two dimensional systems which are more difficult to investigate. A study of this system will also test new theoretical techniques and recent predictions. The principal investigator is experienced and well-regarded in this field. This equipment will enhance considerably the research supported by the Low Temperature Physics Program.
