  The effect of interchain hopping and interaction on Anderson localization has
been investigated for two coupled chains of spinless fermions with nearest
neighbor interaction. Using the renormalization group method, we find that
interchain hopping plays a significant role when the correlation gap induced by
the interplay of interchain hopping and intrachain interaction becomes larger
than the Anderson localization energy scale induced by impurities. The strong
competition between localization and delocalization is examined for attractive
interaction.
