Tests of optical vortex detection based on the Talbot effect at fractional Talbot lengths and with grating rotation: realization for practical uses

The optical vortex (OV) beam which has orbital angular momentum states was detected using the Talbot effect. The results clearly demonstrated the identification of the order and charge of the vortices. However, this technical detection was performed at the Talbot length and multiples thereof. This detection technique is now extended to fractional Talbot lengths. The results confirm that the best measurement contrast is still at periodic multiples of the Talbot length. In addition, the grating rotation has been realized. The grating rotation, that is, the rotation of the interference fringes, has no effect on the tilted dark stripes used to determine the order and charge of the OV beam. The direction of the tilted dark stripes is still aligned with the interference patterns. This makes the Talbot detection method more convenient and flexible for uses in optical applications

Wave and particle in molecular interference lithography

The wave-particle duality of massive objects is a cornerstone of quantum physics and a key property of many modern tools such as electron microscopy, neutron diffraction or atom interferometry. Here we report on the first experimental demonstration of quantum interference lithography with complex molecules. Molecular matter-wave interference patterns are deposited onto a reconstructed Si(111) 7x7 surface and imaged using scanning tunneling microscopy. Thereby both the particle and the quantum wave character of the molecules can be visualized in one and the same image. This new approach to nanolithography therefore also represents a sensitive new detection scheme for quantum interference experiments. <br/

Thermal and electrical properties of porphyrin derivatives and their relevance for molecule interferometry

The authors present new measurements of thermal and electrical properties for two porphyrin derivatives. They determine their sublimation enthalpy from the temperature dependence of the effusive beam intensity. The authors study H2TPP and Fe(TPP)Cl in matter-wave interferometry. Both molecules have nearly equal de Broglie wavelengths but different internal characteristics: only Fe(TPP)Cl exhibits an electric dipole moment of about 2.7?D and the authors discuss its influence on the molecular interference pattern. The authors add an external electric force field to the interferometer and use it to measure the scalar polarizability. They compare their experimental values ?(H2TPP) = 105±4±6?Å3 and ?(Fe(TPP)Cl) = 102±9±6?Å3 to ab initio calculations and they discuss the influence of thermal excitations on the polarizability.Kavli Institute of NanoscienceApplied Science

Gas phase sorting of fullerenes, polypeptides and carbon nanotubes

We discuss the Stark deflectometry of micro-modulated molecular beams for the enrichment of biomolecular isomers as well as single-wall carbon nanotubes, and we demonstrate the working principle of this idea with fullerenes. The sorting is based on the species-dependent susceptibility-to-mass ratio ?/m. The device is compatible with a high molecular throughput, and the spatial micro-modulation of the beam permits one to obtain a fine spatial resolution and a high sorting sensitivity