Vortex radiation from a single emitter in a chiral plasmonic nanocavity

Manipulating single emitter radiation is essential for quantum information science. Significant progress has been made in enhancing the radiation efficiency and directivity by coupling quantum emitters with microcavities and plasmonic antennas. However, there has been a great challenge to generate complex radiation patterns such as vortex beam from a single emitter. Here, we report a chiral plasmonic nanocavity, which provides a strong local chiral vacuum field at an exceptional point. We show that a single linear dipole emitter embedded in the nanocavity will radiate to vortex beam via anomalous spontaneous emission with a Purcell enhancement factor up to similar to 1000. Our scheme provides a new field manipulation method for chiral quantum optics and vortex lasers at the nanoscale.

Automated summary

Manipulating single emitter radiation is important for quantum information science. Coupling quantum emitters with microcavities and plasmonic antennas has been successful in enhancing radiation efficiency and directivity. However, generating complex radiation patterns such as vortex beams from a single emitter has been challenging. Here, researchers report a chiral plasmonic nanocavity that provides a strong local chiral vacuum field, enabling the generation of vortex beams through anomalous spontaneous emission. The scheme offers a new method for field manipulation in chiral quantum optics and nanoscale vortex lasers.