Unveiling the emergence of topological quantum phase transitions in the bidirectional transport of carriers through helical edge states in bismuth selenide

Abstract

Abstract Dynamically induced nontrivial band topology in the electronic structure of materials is increasingly being utilized as a primary resource for developing the quantum advantage in emerging technologies. This makes it a fundamental imperative in contemporary condensed matter physics to obtain a deep understanding of the emergence of topological phases during carrier transport in topological matter. In this paper, we have employed a combination of theoretical and computational methods to investigate the emergence of topological quantum transport phases in bismuth selenide and its bias-dependent characteristics by implementing a scalable numerical renormalization group strategy for the carrier transport state. We unravel the emergence of topological quantum phase transitions for carriers hosted on the (001) surface of bismuth selenide because of lattice sublattice asymmetry and spin-orbit coupling and show how the tunnelling transport through the helical surface state is protected against symmetry-breaking perturbations. Our key findings are as follows: (i) charge carriers in bismuth selenide flow bidirectionally through the helical edge states, (ii) the ballistic transport phase undergoes a topological to trivial dynamical phase transition when time reversal symmetry is broken due to an application of a phenomenological field, which may be realized experimentally by impurity doping with ferromagnetic species (iii) quasiparticle interference mediates a transition between different topological quantum phases. These insights are crucial in the rational design of materials for use as interconnects in miniaturized circuits, and manipulation protocols for realizing spontaneous carrier conduction channels using the topological edge states in devices for energy-efficient and lossless transport in microelectronic applications.