Optical properties of nanowire plasmonic waveguides

Contacts:

Andrei Lavrinenko, DTU Fotonik 4525-6392 (alav@fotonik.dtu.dk)

Alexandra Boltasseva, DTU Fotonik, 4525-6368 (albo@fotonik.dtu.dk)

Surface plasmon polaritons (SPPs) are quasi two-dimensional electromagnetic waves propagating along a dielectric-metal interface. Today, SPPs are being explored intensely for their potential applications in optics [1], photonic (plasmonic) integrated circuits, biological and chemical sensing, nano-lithography, magneto-optic data storage, solar cells, light generation and microscopy as well as being used for studies of fundamental issues like light localization [2], quantum optics and entanglement [3].

In this project, we will focus on the SPP propagation along symmetrical nm-sized metal nanowires. For such plasmonic waveguide, we will study so-called dispersion and transmission characteristics of the waveguides. A dispersion diagram usually specifies types of electromagnetic waves that can propagate in a waveguide by connecting their temporal (frequency) and spatial (propagation constant or wave vector) parameters. These waves are called the modes of the waveguide. Transmission of the waveguide is convenient to define through losses per unit length. Usually we can determine losses by simulating transmission through waveguides of different length. It is very important for the nanowires particularly, because all metals possess large losses on optical frequencies. However, due to sizes of nanowires (100 nm x 100 nm in the cross section) losses might be comparatively small.

The project will be carried at DTU Fotonik where you will take part in exciting and extensive ongoing research on advanced optics and nanotechnology.

[1]        W. L. Barnes, A. Dereux, and T. W. Ebbesen, "Surface plasmon subwavelength optics" Nature 424, 824 (2003).

[2]        S. I. Bozhevolnyi, V. S. Volkov, K. Leosson, and A. Boltasseva, "Surface plasmon polariton waveguiding in random surface nanostructures" Journal of Microscopy 209, 209 (2003).

[3]        E. Altewischer, M. P. v. Exter, and J. P. Woerdman, "Plasmon-assisted transmission of entangled photons" Nature 418, 304 (2002).