Auto-tuning, manipulation and braiding of topological quantum bits in tapered nanowire networks

Informacje na temat projektu

TopoTapered

Identyfikator umowy o grant: 101067680

DOI

10.3030/101067680

Realizacja projektu zakończyła się 7 Kwietnia 2025

Data podpisania przez KE 27 Lutego 2023

Data rozpoczęcia 1 Sierpnia 2023

Data zakończenia 31 Lipca 2025

Finansowanie w ramach

• European Research Council (ERC)

Koszt całkowity

Brak danych

Wkład UE

€ 150 000,00

Koordynowany przez

WEIZMANN INSTITUTE OF SCIENCE
Israel

Periodic Reporting for period 1 - TopoTapered (Auto-tuning, manipulation and braiding of topological quantum bits in tapered nanowire networks)

Okres sprawozdawczy: 2023-08-01 do 2025-07-31

Podsumowanie kontekstu i ogólnych celów projektu

The goal of the TopoTapered PoC project was to establish tapered nanowires as a viable, robust technology to auto-tune Majorana zero modes (MZMs), transport, and braid them towards quantum computation. The formation of MZMs in quasi-one dimensional semiconducting nanowires necessitates satisfying multiple conditions: The semiconductor has strong spin-orbit coupling; The chemical potential is tuned sufficiently close to the Kramer’s degeneracy throughout the topological segment (sufficiently low disorder); The induced superconducting gap is larger than the Zeeman gap opened by a properly aligned magnetic field; Spatial manipulation of the MZMs has to be adiabatic to remain in the topological groundstate. Tapered nanowires assist in achieving two of these requirements: Tapering modulates the subband quantization along the nanowires and with it the energy of the Kramer’s degeneracy such that they cross the chemical potential at segments along the nanowire without global fine tuning; Application of a global backgate results in sliding of the induced topological segments enabling continuous adiabatic transportation of the MZMs.

Prace wykonane od początku projektu do końca okresu sprawozdawczego oraz najważniejsze dotychczasowe rezultaty

We have successfully demonstrated the advantage of tapered nanowires in tuning their spectroscopic properties. We have grown tapered nanowires with a diameter that gradually varies along the nanowire axis. We have imaged the quasi-local spectroscopy of the electronic subbands using scanning tunneling microscopy.

Innowacyjność oraz oczekiwany potencjalny wpływ (w tym dotychczasowe znaczenie społeczno-gospodarcze i szersze implikacje społeczne projektu)

The main challenge towards the implementation of our technology has remained the convincing and robust demonstration of MZMs in such hybrid semiconducting-superconducting nanowire systems, which is a prerequisite for the implementation of tapering.

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