Descripción del proyecto
Un nuevo tipo de cúbit para una protección de la información cuántica que consuma menos recursos
Los sistemas cuánticos pueden existir en estados frágiles que finalmente se eliminan por las interacciones con el medio ambiente. La protección de estos estados es fundamental para el futuro de la computación cuántica. Aunque la corrección de errores cuánticos ofrece una solución, requiere una gran cantidad de recursos. El proyecto ECLIPSE, financiado con fondos europeos, se propone abordar este problema mediante la protección de la información cuántica en un nuevo tipo de cúbit con dos especificidades cruciales. En primer lugar, la codificación se llevará a cabo en un único circuito resonador superconductor cuyo infinito espacio dimensional de Hilbert puede reemplazar los grandes registros de cúbits físicos. En segundo lugar, este cúbit se alimentará por radiofrecuencia y se intercambiarán continuamente fotones con un depósito. Los circuitos desarrollados manipularán los estados cuánticos de la luz. Este proyecto podría mejorar la protección de la información cuántica en los futuros sistemas cuánticos.
Objetivo
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.
Ámbito científico
- 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
Palabras clave
Programa(s)
Régimen de financiación
ERC-STG - Starting GrantInstitución de acogida
75272 Paris
Francia