The short-wave infrared range is highly significant for spectroscopic sensing and upcoming optical communication applications. Integrating active and passive photonic components is essential to achieve compact optical solutions. In this paper, we show, for the first time to our knowledge, a wavelength-selective detection system based on the heterogeneous integration of two grating-coupled InGaAs photodetectors operating at the 2µm wave band, with a wavelength selectivity provided by a dual-channel Mach-Zehnder interferometer fabricated using a silicon-on-insulator (SOI) wafer.
View Article and Find Full Text PDFA novel programmable implantable neurostimulation platform based on photonic power transfer has been developed for various clinical applications with the main focus of being safe to use with MRI scanners. The wires usually conveying electrical current from the neurostimulator to the electrodes are replaced by optical fibers. Photovoltaic cells at the tip of the fibers convert laser light to biphasic electrical impulses together with feedback signals with 54% efficiency.
View Article and Find Full Text PDFBackground: Recent literature shows that most practicing psychiatrists do not receive training in measurement-based care (MBC). Among the primary barriers to MBC implementation are the lack of formal training and curriculums. We present the first comprehensive MBC curriculum for use in adult psychiatric practice, and describe how the curriculum is adapted and implemented in psychiatry residency training programs.
View Article and Find Full Text PDFThe authors define measurement-based care (MBC) in psychiatry as the use of validated clinical measurement instruments to objectify the assessment, treatment, and clinical outcomes, including efficacy, safety, tolerability, functioning, and quality of life, in patients with psychiatric disorders. MBC includes two processes: routine assessments, such as measuring the severity of symptoms with rating scales, and the use of assessments in decision-making. MBC implementation was tested in the Texas Medication Algorithm Project and the German Algorithm Project and has been shown to improve patient outcomes.
View Article and Find Full Text PDFTransition metal nitrides are promising alternative plasmonic materials to noble metals for data storage applications as they exhibit localized surface plasmon resonances and have high melting temperatures. Here, angle dependent spectral measurements of the plasmonic resonances of nanodisk arrays made from titanium nitride are examined. Polarized light is used to excite the quadrupole and higher order resonance plasmonic modes which are required in the state-of-the-art designs of near-field transducers used in plasmonic enhanced magnetic recording.
View Article and Find Full Text PDFHybrid plasmonic lasers provide deep subwavelength optical confinement, strongly enhanced light-matter interaction and together with nanoscale footprint promise new applications in optical communication, biosensing, and photolithography. The subwavelength hybrid plasmonic lasers reported so far often use bottom-up grown nanowires, nanorods, and nanosquares, making it difficult to integrate these devices into industry-relevant high density plasmonic circuits. Here, we report the first experimental demonstration of AlGaInP based, red-emitting hybrid plasmonic lasers at room temperature using lithography based fabrication processes.
View Article and Find Full Text PDFIntegrated plasmonic sources and detectors are imperative in the practical development of plasmonic circuitry for bio- and chemical sensing, nanoscale optical information processing, as well as transducers for high-density optical data storage. Here we show that vertical-cavity surface-emitting lasers (VCSELs) can be employed as an on-chip, electrically pumped source or detector of plasmonic signals, when operated in forward or reverse bias, respectively. To this end, we experimentally demonstrate surface plasmon polariton excitation, waveguiding, frequency conversion and detection on a VCSEL-based plasmonic platform.
View Article and Find Full Text PDFSingle and multi-layer passive optical interconnects using single mode polymer waveguides are demonstrated using UV nano-imprint lithography. The fabrication tolerances associated with imprint lithography are investigated and we show a way to experimentally quantify a small variation in index contrast between core and cladding of fabricated devices. 1x2 splitting devices based on directional couplers and multimode interference interferometers are demonstrated to have less than 0.
View Article and Find Full Text PDFA sub-wavelength grating-based photonic crystal sensor is designed to excite two spectrally and spatially different guided mode resonances that have distinctive electric field distributions. We present and validate the uni-polarized dual resonance approach to separating bulk index perturbations from surface-binding events in a single measurement by monitoring the resonance wavelength shifts. This self-referencing method will reduce errors in the measurement of biomolecule binding events on sensor surfaces in a perturbed environmental background.
View Article and Find Full Text PDFWafer-scale nano-fabrication of silicon nitride (Si x N y ) photonic crystal (PhC) structures on glass (quartz) substrates is demonstrated using a thin (30 nm) chromium (Cr) layer as the hard mask for transferring the electron beam lithography (EBL) defined resist patterns. The use of the thin Cr layer not only solves the charging effect during the EBL on the insulating substrate, but also facilitates high aspect ratio PhCs by acting as a hard mask while deep etching into the Si x N y . A very high aspect ratio of 10:1 on a 60 nm wide grating structure has been achieved while preserving the quality of the flat top of the narrow lines.
View Article and Find Full Text PDFThis review describes recently emerging optical and microfluidic technologies suitable for point-of-care genetic analysis systems. Such systems must rapidly detect hundreds of mutations from biological samples with low DNA concentration. We review optical technologies delivering multiplex sensitivity and compatible with lab-on-chip integration for both tagged and non-tagged optical detection, identifying significant source and detector technology emerging from telecommunications technology.
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