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Series

Portland State University

2019

Atomic, Molecular and Optical Physics

Articles 1 - 2 of 2

Full-Text Articles in Physics

Photoemission Electron Microscopy To Characterize Slow Light In A Photonic Crystal Line Defect, Theodore Stedmark, Rolf Könenkamp Jan 2019

Photoemission Electron Microscopy To Characterize Slow Light In A Photonic Crystal Line Defect, Theodore Stedmark, Rolf Könenkamp

Physics Faculty Publications and Presentations

Using femtosecond nonlinear photoemission electron microscopy (PEEM) we provide a detailed characterization of slow light in a small-size asymmetric photonic crystal structure. We show that PEEM is capable of providing a unique description of the light propagation in such structures by direct imaging of the guided mode. This noninvasive characterization technique allows modal properties such as effective index, phase velocities, and group velocities to be determined. Combining experimental results with finite element method simulation calculations, we study slow light phenomena in a photonic crystal defect mode, and we produce a comprehensive picture of the mechanisms behind it. Our results illustrate …


Imaging Technologies And Strategies For Detection Of Extant Extraterrestrial Microorganisms, Jay Nadeau, Manuel Bedrossian, Chris Lindensmith Jan 2019

Imaging Technologies And Strategies For Detection Of Extant Extraterrestrial Microorganisms, Jay Nadeau, Manuel Bedrossian, Chris Lindensmith

Physics Faculty Publications and Presentations

There is no reductionist definition of life, so the way organisms look, behave, and move is the most definitive way to identify extraterrestrial life. Life elsewhere in the Solar System is likely to be microbial, but no microscope capable of imaging prokaryotic life has ever flown on a lander mission to a habitable planet. Nonetheless, high-resolution microscopes have been developed that are appropriate for planetary exploration. Traditional light microscopy, interferometric microscopy, light-field microscopy, scanning probe microscopy, and electron microscopy are all possible techniques for the detection of extant micro-organisms on Mars and the moons of Jupiter and Saturn. This article …