  The energy spectra of quasi-one dimensional quasiperiodic ladder networks are
analyzed within a tight binding description. In particular, we show that if a
selected set of sites in each strand of a ladder is tunnel-coupled to quantum
dots attached from a side, absolutely continuous subbands can be generated in
the spectrum if one tunes the dot potential and the dot-strand coupling
appropriately. Typical cases with two and three strand Fibonacci ladders in the
off diagonal model are discussed in details. We also discuss the possibility of
re-entrant insulator-metal transition for a general n-strand ladder network
when n becomes large. The observations remain valid even in the case of a
disordered ladder network with the same constituents. The results are
analytically exact.
