[Show abstract][Hide abstract] ABSTRACT: Using microscopic imaging, we study the generation and propagation of beams of surface plasmons (SPs) on a hexagonal metal nanohole array. We discuss the wavelength-dependent propagation, a Fano-type interference and the possibility to generate focused SP beams. Prominent forking of these beams is attributed to resonant (Bragg) scattering from consecutive lattice planes. This claim is supported by a coupled-mode model.
Preview · Article · Apr 2006 · New Journal of Physics
[Show abstract][Hide abstract] ABSTRACT: By analyzing entangled photon states in terms of high-dimensional
spatial mode superpositions, it becomes feasible to expose
high-dimensional entanglement, and even the nonlocality of twin photons.
To this end, a proper analyzer should be designed that is capable of
handling a large number of spatial modes, while still being convenient
to use in an experiment. We compare two variants of a high-dimensional
spatial mode analyzer on the basis of classical and quantum
considerations. These analyzers have been tested in classical optical
No preview · Article · Mar 2006 · Physical Review A
[Show abstract][Hide abstract] ABSTRACT: The singular nature of a noninteger spiral phase plate allows easy manipulation of spatial degrees of freedom of photon states. Using two such devices, we have observed very high-dimensional spatial entanglement of twin photons generated by spontaneous parametric down-conversion.
Preview · Article · Jan 2006 · Physical Review Letters
[Show abstract][Hide abstract] ABSTRACT: The singular nature of a non-integer spiral phase plate allows easy manipulation of spatial superposition states. In this way we have observed very high dimensional (D>=3700) spatial entanglement of twin photons generated by SPDC.
[Show abstract][Hide abstract] ABSTRACT: Measurement of the point-spread function of metal nanohole arrays by using microscopic imaging reveals two contributions. The first of these is due to propagating resonant surface plasmons and the second to nonresonant transmission through the holes. We observe a Fano-type interference between these contributions.
[Show abstract][Hide abstract] ABSTRACT: Measurements of the optical near-field transmission of square and hexagonal nanohole arrays are performed, by making a magnified image of the backside of the hole array with a normal microscope objective. In these measurements it can be observed the surface plasmon (SP) propagation directly by strongly focussing the illumination spot on the array down to a size smaller than the SP propagation length.