Influence of the atmosphere on the phosphorescence of a brominated diphenylphosphine oxide-ethyl naphthaleneimide dyad.

The molecular dyad diphenylphosphine-ethyl bromine naphthaleneimide (Br-DPPENI) emits strong fluorescence and phosphorescence. We studied the intensity and lifetime of the phosphorescence of Br-DPPENI embedded in PMMA films in atmospheres of air, He, Ar, N, and O as a function of pressure between vacuum and ambient pressure (1 bar). The experiment was performed in the frequency domain with a two-channel lock-in amplifier, and the data were analyzed with the polar plot or phasor technique.

Confinement templates for hierarchical nanoparticle alignment prepared by azobenzene-based surface relief gratings.

Alignment of nanoparticles to hierarchical periodic structures is an emerging field in the development of patterned surfaces. Common alignment methods are based on templates that guide particle self-assembly. These can be formed using lithographic methods offering an almost free choice of the motif, while being expensive and time-consuming for large-scale production.

Micro-Refractometry and Local-Field Mapping with Single Molecules.

The refractive index n is one of the most important materials parameters of solids and, in recent years, has become the subject of significant interdisciplinary interest, especially in nanostructures and meta-materials. It is, in principle, a macroscopic quantity, so its meaning on a length scale of a few nanometers, i.e.

Athermal Azobenzene-Based Nanoimprint Lithography.

A novel nanoimprint lithography technique based on the photofluidization effect of azobenzene materials is presented. The tunable process allows for imprinting under ambient conditions without crosslinking reactions, so that shrinkage of the resist is avoided. Patterning of surfaces in the regime from micrometers down to 100 nm is demonstrated.

Fluorescence microscopy and spectroscopy of subsurface layer dynamics of polymers with nanometer resolution in the axial direction.

We studied the dynamics in ultrathin subsurface layers of an amorphous polymer by the spectra of single fluorescent molecules embedded into the layer by vapor deposition and subsequent controlled diffusion to the desired depth in ≈0.5 nm steps. The spectral trails of single molecules were recorded at 4.