Condensed Matter Seminar Series
University of Cologne
Majorana Edge Modes in Fermionic Wires coupled by Aharanov-Bohm Cages
We present a concrete route towards the realization of a pair-hopping term between two fermionic wires, with simultaneous exact suppression of pernicious single-particle poisoning, via Aharonov-Bohm Cages. Such interference terms of complex hopping amplitudes are nowadays at hand via synthetic gauge potentials in cold atomic platforms.
We show that, in their presence, nearest-neighbour interactions give rise via Schrieffer-Wolff transformation to an effective Hamiltonian that exhibits a topological phase with zero-energy Majorana-like Edge Modes.
We support the conclusions via field-theory studies and intensive numerical simulations to identify the most favourable parameter regime, and to demonstrate some defining features of the presence of Majorana Edge Modes like:
i) exponentially degenerate ground-states, ii) reviving correlations with sign depending on the parity sector, and iii) doubly-degenerate entanglement spectrum.