title: Generation of nanopores down to 10 nm for use in deep-nulling interferometry.
abstract: Scanning electron microscope images show that it is easy to generate nanopores on polycarbonate membranes with well-defined pore diameters by ion-track perforation and subsequent magnetron sputtering with metal. The size reduction of the nanopores during sputtering with gold is a linear function of time. Images of different angles and from the bottom side of the membrane show that the channels are the smallest very close to the surface of the metal layer, have a conelike shape, and reach about half as much into the polymer membranes as the metal-layer thickness. This topographical pore shape is ideal for use as optically coherent near-field sources in deep-nulling microscopy. We present the first results of significantly improved nulling stabilization in the presence (<2 nm optical pathway difference) and the absence (<0.6 nm optical pathway difference) of the nanoapertures in the focal region of a deep-nulling microscope.
authors.affiliation: Department of Biophysical Chemistry, Institute for Physical and Theoretical Chemistry, University of Braunschweig, 38106 Braunschweig, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Wehling
authors.forename: Wiebke H
authors.initials: WH
authors.lastname: Pohl
authors.forename: Birgit
authors.initials: B
authors.lastname: Gerke
authors.forename: Stephan
authors.initials: S
authors.lastname: Kipp
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Walla
mesh_terms: D007368:Interferometry / Q000295:instrumentation / Q000379:methods; D007834:Lasers; D008027:Light; D008567:Membranes, Artificial; D008670:Metals / Q000737:chemistry; D008855:Microscopy, Electron, Scanning / Q000295:instrumentation / Q000379:methods; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods; D055095:Optics and Photonics; D010316:Particle Size; D011076:Polycarboxylate Cement / Q000737:chemistry; D016062:Porosity; D012680:Sensitivity and Specificity; D013499:Surface Properties
chemical_list: D008567:Membranes, Artificial; D008670:Metals; D011076:Polycarboxylate Cement; C005506:polycarbonate