Towards a Six-Site Kitaev Chain 

Majorana Zero Modes (MZMs) are quasiparticle excitations in superconductor-semiconductor nanostructures that offer a potential avenue toward topological quantum computing. A key property is their nonlocality, which enables the encoding of quantum information that is robust against local perturbations. In recent years, Kitaev chains in arrays of quantum dots have emerged as a promising platform to controllably engineer MZMs. Two- and three-site Kitaev chains have been realized in both nanowires and two-dimensional electron gases, and the robustness of the MZMs that emerge at the Majorana sweet spot has been characterized. The non-local protection that MZMs enjoy should scale exponentially with the number of sites, which motivates the extension to longer arrays. However, the quantum-transport methods used to tune shorter chains to the Majorana sweet spot will be inadequate for larger quantum dot arrays with normal leads only at the edges. In this work we report progress towards extending these chains in a six-site Kitaev chain device.