2D hybrid materials as a platform for topological quantum computing

The topological protection expected to hold in a Majorana qubit promises virtually decoherence-free and fault-tolerant quantum computation. Thanks to material and experimental advances achieved during the last years, realizing and observing individual Majorana zero modes has become routine in multiple research laboratories. Our project will bring research on Majorana modes to the next level in a twofold way.

First, we will develop cleaner InAs-based systems as well as novel InSb systems that allow the integration of multiple Majorana wires. Second, we will optimize fast electronic control and measurements techniques to be directly applied to study the physical properties of Majorana modes and in performing basic quantum operations.The new material system will be based on high quality III-V two-dimensional heterostructures where the superconductor, aluminum, will be grown in-situ, i.e. directly in the molecular beam epitaxy system. The devices we will fabricate and study will include elongated quantum dots hosting Majorana modes and coupled to charge detectors. Fast gate manipulation will allow us to deterministically change the coupling between Majorana modes. With this simple scheme, the braiding statistics of Majorana modes can be investigated, and elementary quantum operations performed. The results of the operations will be read out by changes in the charge state of the system. Here we will investigate and quantify quasiparticle poisoning, and suggest ways how to minimize it.

CONSORTIUM

  • Coordinator: Klaus Ensslin (ETH Zurich, CH)
  • Werner Wegscheider (ETH Zurich, CH)
  • Felix von Oppen (FU Berlin, DE)
  • Fabrizio Nichele (University of Copenhagen, DK)
  • Ville Maisi (University of Lund, SE)
  • Martin Leijnse (University of Lund, SE)