A collaboration between the Equipe Théorie at MPQ and scientists from ETH Zurich and the Flatiron Institute has demonstrated, both theoretically and experimentally, that giant vacuum fields confined in a split-ring resonator cavity can profoundly alter electron-electron interactions in a quantum Hall system.

(Left) Split-ring resonator cavity hovering above a GaAs Hall bar.
(Right) Schematic illustration of cavity-mediated long-range attractive interaction between electrons via virtual photons.

Two striking effects have been observed: a dramatic enhancement of fractional quantum Hall phases and a strong modification of spin splittings (g-factor renormalization). Both effects are explained by cavity-mediated long-range attractive interactions between electrons. The experimental setup uses a mobile, hovering cavity that allows in-situ tuning of the vacuum field strength above a GaAs-based two-dimensional electron gas.

Reference:

Tunable vacuum-field control of fractional and integer quantum Hall phases

Josefine Enkner, Lorenzo Graziotto, Dalin Boriçi, Felice Appugliese, Christian Reichl, Giacomo Scalari, Nicolas Regnault, Werner Wegscheider, Cristiano Ciuti & Jérôme Faist
Nature 641, 884–889 (2025)

Contact: Cristiano Ciuti

See also : ETH communication

 

À lire aussi

On-chip generation of spatial entanglement

On-chip generation of spatial entanglement

The QITE team just published in Phys. Rev. Lett. its work on the generation of spatial entanglement in nonlinear waveguide arrays, in collaboration with C2N and INPHYNI. Combining the generation and manipulation of complex quantum states of light on a single chip is a...

An hybrid III-V / Silicon source of photon pairs

An hybrid III-V / Silicon source of photon pairs

The QITE team of MPQ lab, in collaboration with C2N lab, INPHYNI and STMicroelectronics, has just published its work on the development of integrated hybrid sources of entangled photons in PRX Quantum. Combining the generation and manipulation of quantum states of...