Detailed comparison of injection-seeded and self-seeded performance of a 1060nm gain-switched Fabry-Perot laser diode

We investigate and compare the performance of a gain-switched picosecond Fabry-Perot laser diode operated at 1.06 µm under both injection- and self-seeded conditions. Our experiments show that comparable performance can be obtained for both modes of operation, with the self-seeding arrangement offering overall benefits in terms of reduced system complexity and cost, providing the associated quantization of available pulse repetition rate can be tolerated

Insight from dream and event discussions using the Schredl method of dreamwork in experienced and inexperienced dreamworkers

Practitioners of dreamwork have long understood that exploring dreams has the potential to be a source of insight, but empirical research evidencing this has generally been lacking, especially in non-clinical settings. Additionally, many of the factors that influence dreamwork efficacy remain to be discovered. The present study aimed to provide evidence for the insight-generating potential of dreamwork, and to investigate a potential factor that may influence how effective a dreamwork session is: the level of experience of the dreamer. Participants (29 (15 experienced and 14 inexperienced in dreamwork)) took part in two discussions: a dream discussion and a waking-life event discussion, using the Schredl “Listening to the Dreamer” method of dreamwork and an adapted version of this for discussing waking-life events. Results indicated that dreamwork led to significantly higher levels of Exploration-Insight and Continuity Insight in comparison to a waking-life event discussion. Levels of Personal Insight did not differ between the two conditions, but did not significantly differ from previous experiments’ Personal Insight levels following dream discussion. Experienced and inexperienced participants’ levels of insight were not significantly different. High variability in insight scores indicated that there were large differences between participants in terms of how effective the discussions were for generating insight, but this difference could not be accounted for by experience levels. Insights about changing one’s life correlated with metaphor perception within the dream. These results illustrate the insight-generating potential of dreamwork for some individuals, irrespective of the dreamer’s level of experience, and perhaps suggest that insight for change may come about following perception of metaphors for waking life in the dream

Localization and Interaction Effects in Strongly Underdoped La2-xSrxCuO4

The in-plane magnetoresistance (MR) in La2-xSrxCuO4 films with 0.03 < x < 0.05 has been studied in the temperature range 1.6 K to 100 K, and in magnetic fields up to 14 T, parallel and perpendicular to the CuO2 planes. The behavior of the MR is consistent with a predominant influence of interaction effects at high temperatures, switching gradually to a regime dominated by spin scattering at low T. Weak localization effects are absent. A positive orbital MR appears close to the boundary between the antiferromagnetic and the spin-glass phase, suggesting the onset of Maki-Thompson superconducting fluctuations deep inside the insulating phase.Comment: 4 pages, 3 figures, to appear in Phys. Rev. Letter

Editorial

We use a linear FROG technique based on electro-optic modulation to fully characterise for the first time pulses from a 1.06 µm FP laser diode and design a grating to provide optimum pulse compression

Room temperature spin relaxation in GaAs/AlGaAs multiple quantum wells

We have explored the dependence of electron spin relaxation in undoped GaAs/AlGaAs quantum wells on well width (confinement energy) at 300 K. For wide wells, the relaxation rate tends to the intrinsic bulk value due to the D'yakonov-Perel (DP) mechanism with momentum scattering by phonons. In narrower wells, there is a strong dependence of relaxation rate on well width, as expected for the DP mechanism, but also considerable variation between samples from different sources, which we attribute to differences in sample interface morphology. (C) 1998 American Institute of Physics. [S0003-6951(98)02541-8].</p

Cost effective flat plate photovoltaic modules using light trapping

Work in optical trapping in 'thick films' is described to form a design guide for photovoltaic engineers. A thick optical film can trap light by diffusive reflection and total internal reflection. Light can be propagated reasonably long distances compared with layer thicknesses by this technique. This makes it possible to conduct light from inter-cell and intra-cell areas now not used in photovoltaic modules onto active cell areas