Photons that aren't actually there influence superconductivity
Researchers have found that virtual photons — particles of light that don't really exist but act as if they do — can influence the behavior of superconductors, potentially degrading their performance.
The Discovery
In quantum field theory, even empty space is filled with fields. Virtual photons are excitations of the electromagnetic field that transmit force between particles but can't be directly detected. However, in locations with strong electromagnetic fields, virtual photons are abundant even without real light.
Researchers discovered that these virtual photons can interact with superconducting materials, specifically those placed near boron nitride — a material with hexagonal ring structures similar to graphene.
How It Works
- Boron nitride has anisotropic optical properties: light travels along the plane of its atomic sheets but is blocked perpendicular to them
- When placed near superconductors, the concentrated virtual photons in the boron nitride can influence electron pairing — the mechanism that enables superconductivity
- The effect appears to degrade superconducting performance rather than enhance it
Why It Matters
This is fundamentally a quantum mechanics story rather than a superconductivity breakthrough. But it provides a new tool for studying virtual particle interactions and may eventually help explain why certain superconducting materials perform worse than theory predicts.
The research demonstrates that quantum vacuum effects are not just theoretical curiosities — they have measurable, practical consequences for real materials.
Source: Ars Technica