We describe what we believe to be a novel use of spectral-domain optical coherence reflectometry (SD-OCR) for highly sensitive molecular detection in real time. The SD-OCR sensor allows identification of a sensor surface of interest in an OCR depth scan and monitoring the phase alteration due to molecular interaction at that surface with subnanometer optical thickness sensitivity. We present su...

Polarisation control is demonstrated in circular gainguided top-surface emitting vertical cavity lasers by etching a narrow trench near the cavity aperture. An optimum etch depth exists for which all modes are pinned in a single polarisation. The etch orientation determines the dominant polarisation state of emission by modifying the spontaneous emission coupling into each polarisation state. P...

This paper presents a novel video surveillance approach designed to detect vandal acts occurring on the background of the monitored scene, such as graffiti painting on walls and surfaces, public and private property defacing or etching, unauthorized post sticking. The aim of our approach is to detect this class of events rapidly and robustly. We propose to use two synchronized views to deploy s...

We have studied the blue shift in photoluminescence emission energy of pseudomorphic InGaAs/ GaAs quantum wells grown on patterned ~001! GaAs substrates with grooves and trenches having vertical sidewalls made by dry etching. Dependence of the blue shift, which can be as large as 51 meV, on the direction, feature size, and the etch depth of the patterns as well as the thickness of the buffer la...

Experimental results of the local droplet etching technique for the self-assembled formation of nanoholes and quantum rings on semiconductor surfaces are discussed. Dependent on the sample design and the process parameters, filling of nanoholes in AlGaAs generates strain-free GaAs quantum dots with either broadband optical emission or sharp photoluminescence (PL) lines. Broadband emission is fo...

We propose a silicon Fabry–Perot planar waveguide modulator structure consisting of two Bragg reflectors to form the cavity. The Bragg reflectors are nanoscale trenches in the waveguide fabricated using electron beam lithography and reactive ion etching. Compared to conventional waveguide modulator designs, large modulation depth can be achieved with much smaller modulator length using high-fin...

Depth-dependent magnetism in MnSb(0001) epitaxial films has been studied by combining experimental methods with different surface specificities: polarized neutron reflectivity, x-ray magnetic circular dichroism (XMCD), x-ray resonant magnetic scattering and spin-polarized low energy electron microscopy (SPLEEM). A native oxide ∼4.5 nm thick covers air-exposed samples which increases the film's...

We present a retrospective on the LBNL Positron Emission Mammography (PEM) project, looking back on our design and experiences. The LBNL PEM camera utilizes detector modules that are capable of measuring depth of interaction (DOI) and places them into 4 detector banks in a rectangular geometry. In order to build this camera, we had to develop the DOI detector module, LSO etching, Lumirror-epoxy...