Electrically driven chiral emission from plasmonic tunnel junctions.

Electrically driven tunneling in plasmonic nanohelicoids produces chiral vortex light with more than 0.8 handedness selectivity at the single-particle level.

• Why it matters: Chirality is essential in many physical, chemical, and biological processes, and controlling chiral light at the nanoscale can advance optical technologies and quantum applications.
• What they did: Researchers integrated tunnel junctions with chiral plasmonic nanohelicoids to generate chiral light through resonant excitation of chiral dipolar modes, achieving spin and orbital angular momentum control.
• The result: This approach enables nanoscale photon spin engineering, with potential applications in display technology, quantum information processing, and photochemistry.