Heat current rectification and mobility edges

We investigate how the presence of a single-particle mobility edge in a system can generate strong heat current rectification. Specifically, we study a quadratic bosonic chain subject to a quasi-periodic potential and coupled at its boundaries to spin baths of differing temperature. We find that rectification increases by orders of magnitude depending on the spatial position in the chain of localized eigenstates above the mobility edge. The largest enhancements occur when the coupling of one bath to the system is dominated by a localized eigenstate, while the other bath couples to numerous delocalized eigenstates. By tuning the parameters of the quasi-periodic potential it is thus possible to vary the amplitude, and even invert the direction, of the rectification.