Abstract:

Propagation of surface plasmon polaritons (SPPs), which are transverse magnetic (TM) polarized optical surface waves, along the interface between a metal and a dielectric has attracted significant attention due to its unique optical properties such as a tight confinement below the diffraction limit and a high sensitivity to the surrounding environment. Nowadays study of SPPs that have fascinating applications in photonics and optoelectronics is necessary for students. However, SPPs suffer from large attenuation because of the ohmic losses in the metal layer. This limitation makes an obstacle to use laboratory experiments for teaching students within the Degree in Physics and Master in Advanced Physics whose main objective is an excitation and detection of surface plasmons. The aim of this paper is the design and staging of a simple experiment, using inexpensive optical elements which are easy to find in university laboratories, leading to a straightforward approach for the excitation and propagation of SPPs. In the particular case of our experiment we employ planar waveguides which were manufactured in our research laboratories by embedding semiconductor nanostructures (CdSe with emission in the visible) in PMMA. This nanocomposite was deposited above a gold layer in order to study the surface plasmon propagation. Such setup will enable a student to handily couple a laser beam into the plasmonic waveguide and subsequently to measure and characterize the field waveform at the exit surface.

Keywords:

Surface plasmon polaritons, practical experience, wave guides.