  We prove that the rank of knot Floer homology detects the Hopf links, and
generalize this result further to classify the links of the second smallest
knot Floer homology. We also prove a knot Floer homology analog of
arXiv:1910.04246v1 [math.GT] and give a partial answer to when the equality
holds in the rank inequality between the knot Floer homology of a link and its
sublinks.
