Rare earth ions having both electric and magnetic dipole transitions in emission spectra can be used as local probe to provide information on degree of modification and local distribution of optical electric and magnetic fields in plasmonic systems. In our research, we use highly luminescent organic systems with Eu3+ to study and analyze modification of magnetic and electric dipoles emission in different environment, including systems having plasmonic electric resonance or magnetic resonance in the range of Eu3+ emission, and flat metal. Experimental setup based on selective detection of the particular transition was built and used for probing and mapping of electric and magnetic fields in plasmonic systems and metasurfaces. The method developed can find applications in characterization of plasmonic systems and metamaterials, and engineering of emission properties of rare earth ions and other emitters.
Plasmonics is promising for future electronics as it can combine optical speed of operation with nanoscale size, something which is not possible with traditional optics and electronics . Coupling of photons, plasmonic excitations and electrons is of key importance as it provides opportunities to monitor or control plasmonic nanocircuits electrically.
Spontaneous emission of a dipole can be significantly modified in metamaterials, providing opportunities to engineer
emission rates, yields, spectra, and angular patterns. To better understand specifics of such modifications for electric and
magnetic emitters, we study luminescence of Eu<sup>3+</sup> ions placed in a close vicinity of arrays of gold nanostrips. The
luminescence is strongly polarized, with the preferable polarization parallel to the direction of strips. Polarization
patterns and angular distributions of radiation depend on wavelength, and are different for electric and magnetic dipole
transitions. The results are discussed in terms of different coupling of emitters with radiative and high-loss modes.