Waveguide effect enhancement of local photocurrent in hybrid organic/inorganic solar cells.

The local efficiency of hybrid ZnO-nanorods/C60/ZnPc:C60/MoO3/Ag solar cells, with different nanorods length has been investigated by scanning near-field optical microscopy. Simultaneous spatially resolved measurements of topography and photocurrent suggest a waveguide effect enhancement of the local photocurrent. This interpretation is supported by finite element method simulations of the light propagation in the solar cell.

Role of interactions in the magneto-plasmonic response at the geometrical threshold of surface continuity: publisher's note.

This publisher's note amends the author listing of [Opt. Express26, 32792 (2017)].

Surface plasmons and magneto-optic activity in hexagonal Ni anti-dot arrays.

The influence of surface plasmons on the magneto-optic activity in a two-dimensional hexagonal array is addressed. The experiments were performed using hexagonal array of circular holes in a ferromagnetic Ni film. Well pronounced troughs are observed in the optical reflectivity, resulting from the presence of surface plasmons. The surface plasmons are found to strongly enhance the magneto-optic response (Kerr rotation), as compared to a continuous film of the same composition. The influence of the hexagonal symmetry of the pattern on the coupling between the plasmonic excitations is demonstrated, using optical diffraction measurements and theoretical calculations of the magneto-optic and of the angular dependence of the optical activity.

Ultrafast transport of laser-excited spin-polarized carriers in Au/Fe/MgO(001).

Hot carrier-induced spin dynamics is analyzed in epitaxial Au/Fe/MgO(001) by a time domain approach. We excite a spin current pulse in Fe by 35 fs laser pulses. The transient spin polarization, which is probed at the Au surface by optical second harmonic generation, changes its sign after a few hundred femtoseconds. This is explained by a competition of ballistic and diffusive propagation considering energy-dependent hot carrier relaxation rates. In addition, we observe the decay of the spin polarization within 1 ps, which is associated with the hot carrier spin relaxation time in Au.

Spectroscopy of the shear force interaction in scanning near-field optical microscopy.

Shear force detection is a common method of tip-sample distance control in scanning near-field optical microscopy. Shear force is the force acting on a laterally oscillating probe tip near a surface. Despite its frequent use, the nature of the interaction between tip and sample surface is a matter of debate. In order to investigate the problem, approach curves, i.e. amplitude and phase of the tip oscillation as a function of the tip-sample distance, are studied in terms of a harmonic oscillator model. The extracted force and damping constants are influenced by the substrate material. The character of the interaction ranges from elastic to dissipative. The interaction range is of atomic dimensions with a sharp onset. Between a metal-coated tip and a Cu sample, a power law for the force-distance curve is observed.