A major new study published in Nature Nanotechnology* demonstrates significantly enhanced stability of Majorana zero modes (MZMs) in engineered quantum systems. This research, conducted by a team from Delft University of Technology, Eindhoven University of Technology, Quantum Machines, and the University of Oxford, represents a major step towards fault tolerant quantum computing.
Majorana zero modes are exotic quasiparticles that are theoretically immune to environmental disturbances that cause decoherence in conventional qubits. This inherent stability makes them promising candidates for building robust quantum computers. Achieving sufficiently stable MZMs, however, has been a persistent challenge due to imperfections in traditional materials.
The research team addressed this challenge by constructing a three-site Kitaev chain - a stepping stone towards topological superconductors. They used quantum dots coupled by superconducting segments in hybrid semiconductor-superconductor nanowires, allowing precise control of quantum states. This three-site design provides a 'sweet spot' where the MZMs are more spatially separated, reducing their interactions and enhancing their stability, which is a key advancement.