Fabrication of phase masks from amorphous carbon thin films for electron-beam shaping

• Lukas Grünewald,
• Dagmar Gerthsen and
• Simon Hettler

Beilstein J. Nanotechnol. 2019, 10, 1290–1302, doi:10.3762/bjnano.10.128

• (VBs) are of great interest due to their well-defined orbital angular momentum (OAM) with the topological charge l and the Dirac constant The phase of a VB varies azimuthally upon propagation, where l is equal to the number of turns in the wave front per wavelength [27]. In the center of a VB exists

• diameter of the expected doughnut-shaped VBs increases with topological charge l. Depending on the fine structure of the thickness pattern a symmetric or asymmetric intensity distribution around the l = 0 order beam is visible as expected [28]. Indeed, much of the total intensity is concentrated in the l

• varying intensity. The size of the doughnut-shaped beam profile increases with the topological charge l. Magnified sections for l = −2 to l = 2 for (b) sinusoidal and (c) saw-tooth patterns with linear intensity scale are compared with simulations. (b) The sinusoidal pattern shows good agreement, whereas

Nematic topological defects positionally controlled by geometry and external fields

• Pavlo Kurioz,
• Marko Kralj,
• Bryce S. Murray,
• Charles Rosenblatt and
• Samo Kralj

Beilstein J. Nanotechnol. 2018, 9, 109–118, doi:10.3762/bjnano.9.13

• and external fields on the spatial positioning of nematic topological defects (TDs). In quasi two-dimensional systems we demonstrate that a confinement-enforced total topological charge of m > 1/2 decays into elementary TDs bearing a charge of m = 1/2. These assemble close to the bounding substrate to

• functional nanodevices. Keywords: nanoparticles; nematic liquid crystals; topological charge; topological defects; Introduction Topological defects (TDs) [1] represent an interdisciplinary research area [2] that is of high interest for nearly all branches of science. Due to their topological origin they

• study patterns emerging from the BAC boundary condition. We enforce a total topological charge of strength m inside the circular boundary of radius R. At the boundary we strongly impose the nematic ordering defined by Equation 10. The energy-minimized configurations are plotted in Figure 3 and Figure 4

Nano-contact microscopy of supracrystals

• Adam Sweetman,
• Nicolas Goubet,
• Ioannis Lekkas,
• Marie Paule Pileni and
• Philip Moriarty

Beilstein J. Nanotechnol. 2015, 6, 1229–1236, doi:10.3762/bjnano.6.126

• depends both on the effective dimensionality and the amount of topological/charge disorder in the system. The distribution of nanocrystal connectivity due to this disorder plays an essential role in determining the topological “landscape” for charge transport, which can be affected at the nanoscopic