Biomedical subjects

John D Love

Publications and source records attributed to John D Love.

4 recordsLinked to original sources

PubMed2006

Waveguide analysis of heat-drawn and chemically etched probe tips for scanning near-field optical microscopy.

We analyze two basic aspects of a scanning near-field optical microscope (SNOM) probe's operation: (i) spot-size evolution of the electric field along the probe with and without a metal layer, and (ii) a modal analysis of the SNOM probe, particularly in close proximity to the aperture. A slab waveguide model is utilized to minimize the analytical complexity, yet provides useful quantitative results--including losses associated with the metal coating--which can then be used as design rules.

Computer-Aided Design↗

PubMed2005

Self-aligning method of fiber-to-waveguide pigtailing.

An innovative self-aligning technique for the pigtailing of optical fibers to buried channel planar waveguides is presented, based on selective etching. This technique utilizes a plug-and-socket mechanism that is intrinsically self-aligning and mechanically stable. The processes involved have been specifically designed to facilitate the bulk manufacture of pigtailed single or multiple fibers and waveguides. An optimized alignment geometry for the physical connection of fibers to waveguides is presented.

Journal Article↗

PubMed2005

Symmetry-selective reflection gratings.

We show that gratings can be designed to be symmetry selective, that is, reflecting modes with a particular symmetry. The idea behind a symmetry-selective grating is to replace a grating written over the entire core cross section of a waveguide with a grating that is written only over a part of the core. This new kind of grating exhibits high-order reflectivity and selectivity in comparison with standard gratings and enables the design of more effective and compact wavelength add/drop devices.

Journal Article↗

PubMed2003

Controlled modification and direct characterization of multimode-fiber refractive-index profiles.

A combination of controlled annealing and characterization by scanning probe microscopy (SPM) is used to demonstrate that the refractive-index proffle of a commercially available silica-based optical fiber can be accurately reconfigured for use as an evanescent field sensor. The process relies on the controlled relocation of the silica glass dopants across the fiber cross section through heat treatment and the accurate measurement of the resulting dopant redistribution with SPM and differential etching techniques. The effect of variable annealing along a length of fiber is to produce a mode transformer to couple light from a laser source into the sensing region of the fiber.

Journal Article↗