  Atomic clusters attached to a low-dimensional system, called Fano defects,
produce rich wave interferences. In this work, we analytically found an
enhanced thermoelectric figure-of-merit (ZT) in periodic atomic chains with
Fano defects, compared to those without such defects. We further study
self-assembled DNA-like systems with periodic and quasiperiodically placed Fano
defects by using a real-space renormalization method developed for the
Kubo-Greenwood formula, in which tight-binding and Born models are respectively
used for the electric and lattice thermal conductivities. The results reveal
that the quasiperiodicity could be another ZT-improving factor, whose
long-range disorder inhibits low-frequency acoustic phonons insensitive to
local defects.
