Projektbeschreibung
Eine neue Art von Qubit für einen weniger ressourcenintensiven Schutz von Quanteninformationen
Quantensysteme können in fragilen Zuständen existieren, die letztlich durch Wechselwirkungen mit der Umwelt ausgelöscht werden. Der Schutz solcher Zustände ist für die Zukunft der Quanteninformatik unerlässlich. Auch wenn die Quantenfehlerkorrektur hier eine Lösung bietet, erfordert sie doch enorme Ressourcen. Das EU-finanzierte Projekt ECLIPSE will dieses Problem durch den Schutz von Quanteninformationen in einem neuartigen Qubit mit zwei entscheidenden Besonderheiten angehen. Erstens wird die Kodierung in einem einzigen supraleitenden Schaltungsresonator stattfinden, dessen unendlich dimensionaler Hilbert-Raum große Register physikalischer Qubits ersetzen kann. Zweitens wird dieses Qubit hochfrequenzbetrieben sein und kontinuierlich Photonen mit einem Reservoir austauschen. Die entwickelten Schaltungen werden die Quantenzustände des Lichts manipulieren. Diese Arbeit könnte den Schutz von Quanteninformationen in zukünftigen Quantensystemen voranbringen.
Ziel
Quantum systems can occupy peculiar states, such as superposition or entangled states. These states are intrinsically fragile and eventually get wiped out by inevitable interactions with the environment. Protecting quantum states against decoherence is a formidable and fundamental problem in physics, which is pivotal for the future of quantum computing. The theory of quantum error correction provides a solution, but its current envisioned implementations require daunting resources: a single bit of information is protected by encoding it across tens of thousands of physical qubits.
My proposal is to protect quantum information in an entirely new type of qubit with two key specificities. First, it will be encoded in a single superconducting circuit resonator whose infinite dimensional Hilbert space can replace large registers of physical qubits. Second, this qubit will be rf-powered, continuously exchanging photons with a reservoir. This approach challenges the intuition that a qubit must be isolated from its environment. Instead, the reservoir acts as a feedback loop which continuously and autonomously corrects against errors. This correction takes place at the level of the quantum hardware, and reduces the need for error syndrome measurements which are resource intensive.
The circuits I will develop manipulate quantum states of light, whose utility transcends the long term goal of quantum computing, and can readily be used to probe fundamental properties of matter. In mesoscopic physics where a large number of particles exhibit collective quantum phenomena, the measurement tools to characterize subtle quantum effects are often lacking. Here, I propose to measure the spin entanglement of a single Cooper pair, by coupling a superconductor to a circuit composed of microwave resonators and a carbon nanotube. The spin entanglement can be swapped into microwave photons, which can be detected by deploying the arsenal of quantum limited microwave measurement devices.
Wissenschaftliches Gebiet
- natural sciencesmathematicspure mathematicsalgebralinear algebra
- natural sciencesphysical sciencescondensed matter physicsmesoscopic physics
- engineering and technologyelectrical engineering, electronic engineering, information engineeringelectronic engineeringcomputer hardwarequantum computers
- natural sciencesphysical scienceselectromagnetism and electronicssuperconductivity
- natural sciencesphysical sciencestheoretical physicsparticle physicsphotons
Schlüsselbegriffe
Programm/Programme
Thema/Themen
Finanzierungsplan
ERC-STG - Starting GrantGastgebende Einrichtung
75272 Paris
Frankreich