Université de Neuchâtel

Analysis of the phonon-polariton response of silicon carbide microparticles and nanoparticles by use of the boundary element method

Rockstuhl, Carsten ; Salt, Martin Guy ; Herzig, Hans-Peter

In: Journal of the Optical Society of America B, 2005, vol. 22, no. 2, p. 481-487

We investigate the small-particle phonon-polariton response of several microstructures that are made of silicon carbide (SiC). Phonon polaritons can be excited in a wavelength region between 10 and 12 µm. Simple structures such as elliptical cylinders support phonon polaritons at two wavelengths, which depend on the axis ratio of the particle. In particles with a more irregular shape such as...

Université de Neuchâtel

Theoretical and experimental investigation of phase singularities generated by optical micro- and nano-structures

Rockstuhl, Carsten ; Salt, Martin Guy ; Herzig, Hans-Peter

In: Journal of Optics A: Pure and Applied Optics, 2004, vol. 6, no. 5, p. 271-276

Phase singularities appear in the diffracted far-field of an optical micro-structure if the object is of a sufficient lateral size to induce an appropriate phase delay. We present results that determine the critical dimension of a single phase bar for the generation of dislocations in the far-field. Using scalar theory, an analytical equality is derived that must be met by the structure. Because...

Université de Neuchâtel

Investigation of the basic properties of phase singularities generated by a phase bar or trench

Rockstuhl, Carsten ; Salt, Martin Guy ; Herzig, Hans-Peter

In: Optics Communications, 2004, vol. 235, no. 1-3, p. 11-21

In the present paper, we determine the conditions necessary for the generation of phase singularities in the far-field by a phase bar or a trench. The ultimate goal of our work is to link object parameters to a topological distribution of pairs of singularities. We apply scalar theory and show that objects smaller than the diffraction limit are not capable of generating singularities....