Tunable boson-assisted finite-range interaction and engineering Majorana corner modes in optical lattices

TL;DR

This paper proposes a feasible method to create tunable, finite-range interactions between ultracold spinless fermions in optical lattices using bosons, enabling the exploration of Majorana corner modes without complex gauge fields.

Contribution

It introduces a controllable scheme for finite-range interactions in ultracold atoms, facilitating the study of topological phases like Majorana modes without requiring artificial gauge fields.

Findings

Tunable interaction strength from repulsive to attractive regimes.

Finite-range interaction controlled by boson hopping.

Potential to realize Majorana corner modes in optical lattices.

Abstract

Nonlocal interaction between ultracold atoms trapped in optical lattices can give rise to interesting quantum many-body phenomena. However, its realization usually demands unconventional techniques, for example the artificial gauge fields or higher-orbit Feshbach resonances, and is not highly controllable. Here, we propose a valid and feasible scheme for realizing a tunable finite-range interaction for spinless fermions immersed into the bath of bosons. The strength of the effective interaction for the fermionic subsystem is artificially tunable by manipulating bosons, ranging from the repulsive to attractive regime. And the interaction distance is locked to the hopping of bosons, making the finite-range interaction perfectly clean for the fermionic subsystem. Specifically we find that, by introducing an additional staggered hopping of bosons, the proposal is readily applied to search the Majorana corner modes in such a spinless system, without implementation of complex artificial gauge fields, which is totally distinct from existing results reported in spinful systems. Therefore this scheme provides a potential platform for exploring the unconventional topological superfluids and other nontrivial phases induced by long-range interactions in ultracold atoms.