Near-field observation of light propagation in nanocoax waveguides.

Observation of amplitude and phase in ridge and photonic crystal waveguides operating at 1.55 microm by use of heterodyne scanning near-field optical microscopy.

We apply heterodyne scanning near-field optical microscopy (SNOM) to observe with subwavelength resolution the amplitude and phase of optical fields propagating in several microfabricated waveguide devices operating around the 1.55 microm wavelength. Good agreement between the SNOM measurements and predicted optical mode propagation characteristics in standard ridge waveguides demonstrates the ...

Near-field observation of evanescent light wave coupling in subwavelength optical waveguides

Meta-material photonic funnels for sub-diffraction light compression and propagation

We present waveguides with photonic crystal cores, supporting energy propagation in subwavelength regions with a mode structure similar to that in telecom fibers. We design meta-materials for near-, mid-, and far-IR frequencies, and demonstrate efficient energy transfer to and from regions smaller than 1/25-th of the wavelength. Both positiveand negative-refractive index light transmissions are...

Quantitative Comparison of Analytical solution and Finite Element Method for investigation of Near-Infrared Light Propagation in Brain Tissue Model

Introduction: Functional Near-Infrared Spectroscopy (fNIRS) is an imaging method in which light source and detector are installed on the head; consequently, re-emission of light from human skin contains information about cerebral hemodynamic alteration. The spatial probability distribution profile of photons penetrating tissue at a source spot, scattering into the tissue, and being released at ...

Near-field characterization of guided polariton propagation and cutoff in surface plasmon waveguides

We present a series of near-field experiments characterizing cutoff for the three lowest order leaky surface plasmon modes supported by Au stripes on glass substrates. These studies demonstrate that the propagation of light along surface plasmon waveguides is mediated by a discrete number of guided polariton modes as well as a continuum of radiation modes. To distinguish the contribution of the...