Dynamics and Fusion of Majorana Zero Modes in Quantum-dot based Interacting Kitaev Chains

TL;DR

This paper explores the dynamics, fusion, and exotic multi-site Majorana zero modes in quantum-dot based Kitaev chains, with implications for topological quantum computing and braiding in Y-junctions.

Contribution

It provides a theoretical analysis of Majorana zero modes at the sweet spot in quantum-dot Kitaev chains, including discovery of multi-site MZMs and fusion behaviors relevant for quantum computation.

Findings

Majorana modes can be manipulated at the sweet spot $t_h = b4$

Discovery of exotic multi-site MZMs in Y-shaped wires

Demonstration of non-trivial fusion processes in canonical Kitaev wires

Abstract

Motivated by the recent experimental realization of a minimal Kitaev chain in quantum dot systems, we present our theoretical findings on the dynamics and fusion of MZMs at or near the $``$sweet spot" $t_h = \Delta$ (where the fermionic hopping $t_h$ and superconducting coupling $\Delta$ are equal). We investigated the dynamics and fusion of MZMs using time-dependent real-space local density-of-states methods. The movement of Majoranas and the detection of fusion channels are crucial for topological quantum computations. Additionally, we discuss our recent discovery of exotic $``$multi-site" MZMs in $Y$-shaped Kitaev wires, which is important for the potential braiding of Majoranas in $Y$-junctions formed from arrays of quantum dots. Finally, we present results on "non-trivial" fusion using canonical Kitaev wires at the sweet spot.