Weak Coupling of Superfluid Helium Confined to Zero Dimensions

Measurements of the specific heat of liquid helium confined in all three spatial dimensions shows an anomalous behavior that suggests a coupling of individual regions of superfluid. This coupling is thought to occur through the shallow channels used to fill the boxes used as confinement structures. This may be evidence of a proximity effect where helium in the larger boxes modifies the behavior of the helium in the smaller channels and vice versa. Thus, the behavior of both regions is modified beyond typical finite-size effects.