The development of future quantum photonic technologies will rely heavily on our ability to interact efficiently with single quantum emitters. This includes collecting most of the light emitted by such emitters and also exciting them with a high probability. To date, various photonic structures such as micropillars, photonic crystals, and plasmonic antennas have been implemented with these objectives in mind. The parabolic reflector, which is ubiquitous in radio and microwave engineering, has exactly the desired characteristics. For an isotropic source placed at its focal point, the collected emission will be emitted as a collimated beam along the paraboloid axis. Given that they rely on geometric properties of the parabolic surface, parabolic antennas additionally tend to be broadband. Very recently, these ideas have been translated into the realm of nanophotonics, with the fabrication of wavelength-scale parabolic reflectors around single emitters. In this case, interference effects play an important role. Penketh and coworkers have numerically studied how wavelength-scale reflectors can modify the radiation pattern and radiated power of dipole emitters compared to the classic ray optics picture. They have found that in most cases, the optimal emitter position differs significantly from the focal point. In addition, interference between the reflected waves and the dipole source can modify the total power radiated by the source. In some cases, the radiated power can even exceed that expected from ray optics. The findings of this work will serve as an excellent guide for the future implementation of wavelength-scale parabolic antennas.

---

---

 Add Comment

You must log in to add comments.