Multiple topological phase transitions in double-bridged polyacene polymers: Ab initio parametrized stacked Su-Schrieffer-Heeger model

Polyacene polymers are promising organic one-dimensional materials for optoelectronic and energy conversion applications that can host non-trivial topologically insulating phases, without the need of spin orbit coupling. In this work, by using ab-initio methods, we show that, in its multi- bridged configuration, it is possible to tune their topological phase by varying the bridges’ number and relative position. Moreover, we show that these multi-bridged polymers can be described by a stacked Su-Schrieffer-Heeger (SSH) model, where inter-chain hoppings and next-nearest neighbour interactions play a crucial role in stabilizing multitude of non-trivial topologically insulating phases. The generality of this model is such that it can be used to describe any couple of interacting SSH chains.