Laser operation of a GaN vertical cavity surface emitting laser (VCSEL) is demonstrated under optical pumping with a nanoporous distributed Bragg reflector (DBR). High reflectivity, approaching 100%, is obtained due to the high index-contrast of the nanoporous DBR. The VCSEL system exhibits low threshold power density due to the formation of high Q-factor cavity, which shows the potential of na...

Cephalopods possess a sophisticated array of mechanisms to achieve camouflage in dynamic underwater environments. While active mechanisms such as chromatophore patterning and body posturing are well known, passive mechanisms such as manipulating light with highly evolved reflectors may also play an important role. To explore the contribution of passive mechanisms to cephalopod camouflage, we in...

We present a novel high-speed transmitter consisting of a frequency modulated DBR laser and optical filters. The refractive index modulation in the phase control region of the DBR laser allows highspeed frequency modulation. The generated frequency modulated signal is converted to an intensity modulated signal using the edge of the optical filter pass band. We present theoretical simulations of...

Here we numerically and experimentally demonstrate the conversion of normally incident light into the guiding modes of distributed Bragg reflector (DBRs) mirror. By fabricating a gold grating onto a 7.5 pairs TiO2/SiO2 DBR mirror, a series of asymmetrical resonances have been formed at the bandgap range of the DBR mirror. The detailed numerical calculations show that these Fano resonances are a...

Der Kommentar nimmt Stellung zu einem Beitrag von Gabi Reinmann über Qualitätskriterien des design-based research (DBR) in der Bildungsforschung. Er stellt "iterative Forschungsdesigns" infrage, die häufig als zentrales Merkmal DBR betrachtet werden. Als charakteristisch für gestaltungsorientierte Bildungsforschung wird dagegen eine bestimmte Akteurskonstallation dargestellt, bei und -praxis - ...

Number of Papers published in peer-reviewed journals: Final Report: Ultraviolet Polariton Laser Report Title Significant progress was achieved in the epitaxy of deep UV AlN/ AlGaN Bragg mirrors and microcavity structures paving the way to the successful fabrication of vertical cavity emitting laser structures and polariton lasers. For the first time DBRs providing sufficient high reflectivity f...

PURPOSE To evaluate the adverse outcomes after delayed breast reconstruction (DBR) by abdominal advancement flap (AAF) and permanent prosthesis in patients treated with mastectomy due to unilateral breast carcinoma, as well as to determine which factors are predictive for their occurrence. METHODS The study included 155 patients operated at the Institute for Oncology and Radiology of Serbia f...

Curriculum development for distance education (DE) practitioners is more and more focusing on practical requirements and competence development. Delphi and DACUM methods have been used at some universities. However, in the competency-based development area, these methods have been taken over by professional-task-based development in the last decade, which has not been applied in the open and di...

Theory of Constraints has been emerging as an important tool for optimization of manufacturing/service systems. Goldratt in his first book “ The Goal ” gave the introduction on Theory of Constraints and its applications in a factory scenario. A large number of production managers around the globe read this book but only a few could implement it in their plants because the book did not explain t...

We propose a unified framework consisting of a differential bandwidth reservation (DBR) algorithm and a Quality of Service (QoS)-aware admission control scheme to provide QoS guarantees to on-going connections in cellular networks. The differential bandwidth reservation policy uses a sector of cells in making the bandwidth reservation for accepting a new call. Based on the distance of the targe...