A 780-nm-band integrated tunable two-wavelength AlGaAs DBR laser with PN junction heaters was designed and fabricated. Tunable coherent THz wave generation in 0.8-1.2 THz using GaAs photomixers was demonstrated. Keywords-component; DBR lasers; two-wavelength lasers; tunalbe lasers; integrated optoelectoronics; THz-wave generation

This article discusses educational design-based research (DBR) as an emerging paradigm/methodology in educational enquiry that can be used as a mixed-method, problem-oriented research framework, and thus can act as an alternative to other traditional paradigms/methodologies prominent within the Egyptian context of educational enquiry. DBR is often referred to as a long-term research endeavour and

Building on a long research tradition (cf. 1), this paper proposes to apply the distinction between data (information stored in the agent’s mind) and beliefs (information accepted as reliable) to belief revision modeling (cf. 2), in order to integrate belief change in the overall epistemic processing of the agent. As a result, a more comprehensive and complex model of epistemic dynamics is form...

Die Entwicklung von Standards für Design-Based Research (DBR) ist ein Desiderat. Mit meinem Beitrag „Was macht zu Forschung? Debatte um und die vernachlässigte Rolle des Designs“ habe ich zwölf auf den Ebenen Wissenschaftlichkeit Designangemessenheit erarbeitet zur Diskussion gestellt. Drei DBR-Experten haben Einladung zum Austausch angenommen Diskussionsbeiträge verfasst, wichtige Impulse eine...

Dieser Beitrag beleuchtet den forschungsmethodologischen Ansatz des Design-Based Research (DBR) aus der fachdidaktischen Perspektive Geographie. Das Verständnis von Kernelementen und Besonderheiten DBR wird theoretisch diskutiert anhand Erkenntnissen vier geographiedidaktischen DBR-Projekten geschärft konkretisiert. Argumentativ dargelegt werden die Kernelemente: Praxisproblemdefinition, Design...

Semiconductor diode lasers can be used in a variety of applications including telecommunications, displays, solid-state lighting, sensing and printing. Among them, vertical-cavity surface-emitting lasers (VCSELs) are particularly promising. Because they emit light normal to the constituent wafer surface, it is possible to extract light more efficiently and to fabricate two-dimensional device ar...

A low-threshold-current distributed reflector laser consisting of phase-shifted distributed feedback (DFB) grating and quantumwire distributed Bragg reflector (DBR) sections was realized. The device with a DFB length of 150μm, a DBR length of 240μm and a stripe width of 1.5μm achieved a threshold current as low as 1.2mA and a differential quantum efficiency of 13% from the front facet under RT-...

In this work, the spectral properties of distributed Bragg reflector-based photonic crystal (DBR-PhC) structures were studied for near-infrared (NIR) range. Different structural varied to study their effect on quality stopband and appearance resonant dips in reflection spectra DBR-PhC structure. The investigated features included depth PhC holes, hole radius, number elements DBR 11-layered stru...

We have assembled and studied melt-processed all-polymer lasers comprising distributed Bragg reflectors that were fabricated in large sheets using a co-extrusion process and define the cavities for dye-doped compression-molded polymer gain core sheets. Distributed Bragg reflector (DBR) resonators consisting of 128 alternating poly(styrene) (PS) and poly(methyl methacrylate) (PMMA) layers were p...

Apparent personality analysis from short video sequences is a challenging problem in computer vision and multimedia research. In order to capture rich information from both the visual and audio modality of videos, we propose the Deep Bimodal Regression (DBR) framework. In DBR, for the visual modality, we modify the traditional convolutional neural networks for exploiting important visual cues. ...