Motivated by the recent experimental realization of minimal Kitaev chains using quantum dots, we investigate the Majorana zero modes (MZM) in Y-shape Kitaev wires. We solve the associated Kitaev models analytically at the sweet spot (th=Δ) and derive the exact form of MZM wave-functions in this geometry. The novelty of our result is the observation of multi-site MZMs located near the junction center on the nearby edge sites of each leg. This result is important for potential braiding of Majoranas and the performance of Y-junctions made from arrays of quantum dots. Furthermore, we study the stability of local (single-site) and multi-site MZMs modes in the presence of Coulomb repulsion, using density matrix renormalization group theory. Our local density-of-states calculation shows that these multi-site MZMs are as equally topologically protected as the single-site MZMs when in the presence of Coulomb repulsion or when away from the sweet-spot.
@article{arxiv.2306.04081,
title = {Majorana zero modes in Y-shape interacting Kitaev wires},
author = {Bradraj Pandey and Nitin Kaushal and Gonzalo Alvarez and Elbio Dagotto},
journal= {arXiv preprint arXiv:2306.04081},
year = {2023}
}