Now showing items 1-5 of 5
Temporal Airy pulses for controlled high aspect ratio nanomachining of dielectrics
Understanding the interplay between optical pulse parameters and ultrafast material response is critical in achieving efficient and controlled laser nanomachining. In general, the key to initiate material processing is the deposition of a sufficient energy density within the electronic system. In dielectrics this critical energy density corresponds typically to a plasma frequency in the near-IR spectral region. Creating this density instantaneously with ultrashort laser pulses of a few tens of femtoseconds pulse ...
Temperature stability of static and dynamic properties of 1.55 μm quantum dot lasers
Static and dynamic properties of InP-based 1.55 µm quantum dot (QD) lasers were investigated. Due to the reduced size inhomogeneity and a high dot density of the newest generation of 1.55 µm QD gain materials, ridge waveguide lasers (RWG) exhibit improved temperature stability and record-high modulation characteristics. Detailed results are shown for the temperature dependence of static properties including threshold current, voltage-current characteristics, external differential efficiency and emission wavelength. ...
Optical amplification and stability of spiroquaterphenyl compounds and blends
In this contribution, we present a systematic investigation on a series of piroquaterphenyl compounds optimised for solid state lasing in the near ultraviolet (UV). Amplified spontaneous emission (ASE) thresholds in the order of 1 μJ/cm2 are obtained in neat (undiluted) films and blends, with emission peaks at 390 1 nm for unsubstituted and meta-substituted quaterphenyls and 400 4 nm for para-ether substituted quaterphenyls. Mixing with a transparent matrix retains a low threshold, shifts the emission to lower ...
Normative and cognitive influences on female entrepreneurial reluctance at the base of the pyramid - an explorative study of cleaning ladies in Istanbul
(COMSATS, Inst. of Information Technology, 2013)
Previous research has considered entrepreneurship as a way out of poverty and as a chance to foster economic growth. Moreover, specifically start-ups headed by women have played an important role in the economic development and it has been argued that gender-related issues, amongst others, play a significant role for the performance of a country or region. Against this background, this qualitative study explores desires, reluctances and constraints toward entrepreneurial activities of a comparably homogenous group ...
Happy growers! Relationship quality in the German organic apple chain
Relational factors between supply chain actors have been acknowledged to contribute significantly to competitiveness. With the example of the German market for organic apples the suitability of the concept of the Relational View for explaining competitiveness was investigated. Structured interviews were conducted with selected actors of the supply chain. Actors at all levels of the supply chain proved to be highly committed and described their business relations as satisfying and trustful. Strong vertical and horizontal ...