Near field phase mapping exploiting intrinsic oscillations of aperture NSOM probe.

An innovative, simple, compact and low cost approach for phase mapping based on the intrinsic modulation of an aperture Near Field Scanning Optical Microscope probe is analyzed and experimentally demonstrated. Several nanoscale silicon waveguides are phase-mapped using this approach, and the different modes of propagation are obtained via Fourier analysis. The obtained measured results are in good agreement with the effective indexes of the modes calculated by electromagnetic simulations. Owing to its simplicity and effectiveness, the demonstrated system is a potential candidate for integration with current near field systems for the characterization of nanophotonic components and devices.

Near field phase mapping exploiting intrinsic oscillations of aperture NSOM probe

An innovative, simple, compact and low cost approach for phase mapping based on the intrinsic modulation of an aperture Near Field Scanning Optical Microscope probe is analyzed and experimentally demonstrated. Several nanoscale silicon waveguides are phase-mapped using this approach, and the different modes of propagation are obtained via Fourier analysis. The obtained measured results are in good agreement with the effective indexes of the modes calculated by electromagnetic simulations. Owing to its simplicity and effectiveness, the demonstrated system is a potential candidate for integration with current near field systems for the characterization of nanophotonic components and devices. © 2011 Optical Society of America.

Near field phase mapping exploiting intrinsic oscillations of NSOM probe

An innovative, simple compact and low cost approach for phase mapping based on the intrinsic modulation of a Near Field Scanning Optical Microscope probe is analyzed and experimentally demonstrated. © OSA/ CLEO 2011.

Demonstration of submicron square-like silicon waveguide using optimized LOCOS process.

We demonstrate the design, fabrication and experimental characterization of a submicron-scale silicon waveguide that is fabricated by local oxidation of silicon. The use of local oxidation process allows defining the waveguide geometry and obtaining smooth sidewalls. The process can be tuned to precisely control the shape and the dimensions of the waveguide. The fabricated waveguides are measured using near field scanning optical microscope at 1550 nm wavelength. These measurements show mode width of 0.4 µm and effective refractive index of 2.54. Finally, we demonstrate the low loss characteristics of our waveguide by imaging the light scattering using an infrared camera.

Nanoscale mode selector in silicon waveguide for on chip nanofocusing applications.

We demonstrate a nanoscale mode selector supporting the propagation of the first antisymmetric mode of a silicon waveguide. The mode selector is based on embedding a short section of PhC into the waveguide. On the basis of the difference in k-vector distribution between orthogonal waveguide modes, the PhC can be designed to have a band gap for the fundamental mode, while allowing the transmission of the first antisymmetric mode. The device was tested by directly measuring the modal content before and after the PhC section using a near field scanning optical microscope. Extinction ratio was estimated to be approximately 23 dB. Finally, we provide numerical simulations demonstrating strong coupling of the antisymmetric mode to metallic nanotips. On the basis of the results, we believe that the mode selector may become an important building block in the realization of on chip nanofocusing devices.

Experimental demonstration of locally oxidized hybrid silicon-plasmonic waveguide

We experimentally demonstrate a self-aligned approach for the fabrication of nanoscale hybrid silicon-plasmonic waveguide fabricated by local oxidation of silicon (LOCOS). Implementation of the LOCOS technique provides compatibility with standard complementary metal-oxide-semiconductor technology and allows avoiding lateral misalignment between the silicon waveguide and the upper metallic layer. We directly measured the propagation and the coupling loss of the fabricated hybrid waveguide using a near-field scanning optical microscope. The demonstrated structure provides nanoscale confinement of light together with a reasonable propagation length of ∼100 μm. As such, it is expected to become an important building block in future on-chip optoelectronic circuitry. © 2010 American Institute of Physics.

A normal force distance regulation scheme for near-field optical microscopy

A near-field optical microscope (NFOM) has been developed that combines the features of a near-field optical microscope and an atomic force microscope. Improved control over tip-sample separation has led to improved optical imaging and independent surface topography information. The tip oscillation is normal to the sample plane thereby reducing lateral forces - important for nonperturbative imaging of soft samples. Both topographic images and reflection near-field optical images are presented which demonstrate the capability of the system. © 1996 American Institute of Physics.