Quantum Coherence in Superconducting Vortex States
arXiv:2510.19769 · doi:10.1038/s41586-026-10441-7
Abstract
Abrikosov vortices, where the superconducting gap is completely suppressed in the core, are dissipative, semi-classical entities that impact applications from high-current-density wires to superconducting quantum devices. In contrast, we present evidence that vortices trapped in granular superconducting films can behave as two-level systems, exhibiting microsecond-range quantum coherence and energy relaxation times that reach fractions of a millisecond. These findings support recent theoretical modeling of superconductors with granularity on the scale of the coherence length as tunnel junction networks, resulting in gapped vortices. Using the tools of circuit quantum electrodynamics, we perform coherent manipulation and quantum non-demolition readout of vortex states in granular aluminum microwave resonators, heralding new directions for quantum information processing, materials characterization, and sensing.
References in corpus (9)
- Quantum breakdown of superconductivity in low-dimensional materials
- Non-Poissonian Quantum Jumps of a Fluxonium Qubit due to Quasiparticle Excitations
- Microscopic origin of low frequency flux noise in Josephson circuits
- Trapping a single vortex and reducing quasiparticles in a superconducting resonator
- Vortex trapping and expulsion in thin-film YBCO strips
- Electrodynamics of granular aluminum from superconductor to insulator: observation of collective superconducting modes
- Granular superconductors for high kinetic inductance and low loss quantum devices
- Advanced SQUID-on-lever scanning probe for high-sensitivity magnetic microscopy with sub-100-nm spatial resolution
- Quantum Coherence in Superconducting Vortex States