Abstract

Majorana zero modes (MZMs)—spinless, charge-neutral, zero-energy excitations—arise at the boundaries of one-dimensional p-wave superconductors and are promising building blocks for fault-tolerant quantum computing. Candidate platforms include topological insulators, spin–orbit-coupled semiconducting nanowires, iron-based superconductors, and fractional quantum Hall systems. Here we pursue a bottom-up route: semiconductor quantum dots with strong spin–orbit coupling, coupled via superconductors to realize the unit cell of the Kitaev chain [1,2]. Using InSb nanowires clad with epitaxial aluminum half-shells, we engineer fine-tuned paired MZMs within minimal chains, enabling controlled studies of their hybridization, fermion parity, and robustness to disorder and gating [3]. I will present an experimental framework for assembling and characterizing basic Kitaev-chain components in this hybrid platform, followed by systematic “chain-scaling” results that track the evolution from a single unit cell to extended chains [4]. I will conclude with outlook protocols for reading out quantum information in this architecture.

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