The main achievement of the modern plasmonics is the concentration of light into nanospots that are much smaller than the wavelength. Nanospot concentration is beneficial for various applications: biomedical imaging and sensing, optical microscopy with single-molecule resolution, heat assisted magnetic recording (HAMR), QED studies, nanolasing, etc. Until now, plasmonic metal nanoantennae, sub-wavelength apertures or metallic near field concentrators (NFCs) are used for this purpose. The main advantage of the metal NFC is their capabilities to localize plasmonic modes, which can be excited by the incident transverse em wave. However, the metal NFCs have large optic loss so we propose a novel all-dielectric NFC, which allows focusing the light into a sub-wavelength hot nanospot, without the dissipative loss. The detrimental dephasing and thermal effects almost vanishes in the dielectric NFC opening new opportunities in the magnetic recording and quantum plasmonics. The ability to concentrate light is important not only to fundamental physics studies, but also to practical device applications. For example, microcavities can force the atoms or quantum dots to emit spontaneous photons in a desired direction or can provide an environment, where dissipative mechanisms such as spontaneous emission are overcome. The electric field is much enhanced in the proposed new device at the vertex of the dielectric beak, which is attached to the tablet dielectric resonator. The resonator in turn is pumped through the plane waveguide. The electric field is enhanced due to longitudinal polarization of the beak vertex, which is excited by em field of the pumped resonator.
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