High gain broadband plasmonic slot nano-antenna has

\r\nbeen considered. The theory of plasmonic slot nano-antenna (PSNA)

\r\nhas been developed. The analytical model takes into account also the

\r\nelectrical field inside the metal due to imperfectness of metal in

\r\noptical range, as well as numerical investigation based on finite

\r\nelement method (FEM) has been realized. It should be mentioned that

\r\nYagi-Uda configuration improves directivity in the plane of structure.

\r\nIn contrast, in this paper the possibility of directivity improvement of

\r\nproposed PSNA in perpendicular plane of structure by using

\r\nreflection metallic surface placed under the slot in fixed distance has

\r\nbeen demonstrated. It is well known that a directivity improvement

\r\nbrings to the antenna gain increasing. This method of diagram

\r\nimproving is also well known from RF antenna design theory.

\r\nMoreover the improvement of directivity in the perpendicular plane

\r\ngives more flexibility in such application as improving the light and

\r\natom, ion, molecule interactions by using such type of plasmonic slot

\r\nantenna. By the analogy of dipole type optical antennas the widening

\r\nof working wavelengths has been realized by using bowtie geometry

\r\nof slots, which made the antenna broadband.<\/p>\r\n","references":null,"publisher":"World Academy of Science, Engineering and Technology","index":"Open Science Index 101, 2015"}