Description du projet
Une plateforme expérimentale inédite pourrait accélérer les progrès en informatique quantique
Les bits quantiques, ou qubits, sont capables de stocker et traiter beaucoup plus d’informations qu’un bit classique car ils peuvent se trouver dans deux états en même temps. Malheureusement, ces effets quantiques sont très fragiles et toute influence extérieure est susceptible de provoquer l’«effondrement» du qubit. Les scientifiques évoquent désormais des ordinateurs quantiques topologiques qui coderont leurs qubits grâce à un type de quasi-particule dont nous ne sommes même pas sûrs de l’existence. Les propriétés dites topologiques de ces quasi-particules les rendent particulièrement robustes aux interférences extérieures. Le projet TOCINA, financé par l’UE, met au point une nouvelle plateforme expérimentale qui permettra aux scientifiques d’étudier ces principes fondamentaux d’une manière inédite.
Objectif
The key challenge in quantum computation is decoherence - the collapse of a quantum state due to local perturbations. In this proposal we address this challenge by developing a new nanomaterials system, which forms the core of a future topological quantum computer. In a topological quantum bit, information is encoded in Majorana modes, which are topologically protected by a local symmetry and therefore have long coherence times.
In this project we develop a new state of matter -topological crystalline insulator nanowires- in which the topology is defined by the band inversion and the crystal symmetry of the material. Therefore, these topological states should be exceptionally robust. Further, we integrate strong superconductors on these nanowires. These two features together should increase the energy scales of the system compared to current state-of-the-art devices, and therefore lead to stable and electrically-isolated Majorana states.
In this project we develop new crystal growth strategies, which enable to grow out-of-thermodynamic equilibrium structures. We will be the first to employ Molecular Beam Epitaxy (MBE) to precisely tune the SnTe nanowire growth conditions. We use the directionality offered by MBE to shadow-grow superconductors on one nanowire facet. The in-situ ultra-high-vacuum growth of hybrid semiconductor/superconductor devices will result in unprecedented device quality.
Due to the increased energy scales, experiments, which have been unattainable so far, come within reach. We use this new materials platform to demonstrate entanglement of two Majorana modes at the ends of a nanowire. This quantum teleportation is a groundbreaking experiment and is the key of a topological quantum computer.
Champ scientifique
- engineering and technologymaterials engineeringcrystals
- natural sciencesmathematicspure mathematicstopology
- engineering and technologyelectrical engineering, electronic engineering, information engineeringelectronic engineeringcomputer hardwarequantum computers
- natural sciencesphysical scienceselectromagnetism and electronicssemiconductivity
- natural sciencesphysical scienceselectromagnetism and electronicssuperconductivity
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Programme(s)
Thème(s)
Régime de financement
ERC-ADG - Advanced GrantInstitution d’accueil
5612 AE Eindhoven
Pays-Bas