Photoluminescence and attenuation of spray-pyrolysis-deposited erbium-doped Y2O3 planar optical waveguides

Erbium-doped Y20 3 planar optical waveguides have been fabricated by spray-pyrolysis deposition. The attenuation spectrum of the waveguide shows peaks that are due to absorption of the erbium ions. The as-deposited layers also show photoluminescence sharply peaking at 1540 nm with additional Stark splitting. The thin layers of Er 3:Y 203 obtained are promising for the realization of integrated-optic amplifiers and lasers

Design of 1480-nm diode-pumped Er3+-doped integrated optical amplifiers

Erbium-doped Y2O3 integrated optical amplifiers are designed for low-threshold operation and 3 dB amplification. The most important design parameter for minimal threshold, the erbium concentration, is found to have an optimum value of 0.35 at% for a given waveguide structure with 1.0 dB cm-1 background loss. The corresponding threshold power is 7 mW. The pump power to obtain 3 dB gain is found to be 22 mW for an amplifier with an optimum erbium concentration of 0.6 at% and 2.8 cm length. At 30 mW pump power the maximum gain is shown to be 5 dB.\ud \ud Designing is done using a comprehensive numerical model of an erbium-doped integrated optical amplifier. In the model two-dimensional intensity-dependent overlap integrals are used, which allow arbitrary erbium dopant profiles and waveguide crosssections. Concentration-dependent effects such as quenching and upconversion are also included in the model.\ud \ud Input parameters for the model are determined from measurements on an unoptimized Er: Y2O3 optical waveguide amplifier. Amplification simulations and gain measurements of the unoptimized waveguides are found to be in close agreement, providing a sound basis for the design calculations

Bent asymmetric Y-branch integrated optical broadband wavelength multi/demultiplexer

A new integrated optic wavelength multi/demultiplexer based on a bent asymmetric Y-branch is proposed and investigated. The broadband multi/demultiplexer is demonstrated to combine/split 660 nm pump light and 1535 nm signal light with coupling efficiencies of about 85% and 95% respectively, which is useful for erbium doped integrated optic lasers. The bent Y-branch multi/demultiplexer is simple to fabricate and rather insensitive to processing variations

The role of warmth in the experience of hospitality:An exploratory study

To create positive customer experiences, the service industry is increasingly paying attention to hospitality. However, service organisations are in need of tools to improve the experience of hospitality of their customers. What service attributes result in an experience of hospitality? Research on hospitality has thus far focussed on service staff behaviour (Ariffin & Maghzi, 2012; Blain & Lashley, 2014; Tasci & Semrad, 2016). However, there is a lack of knowledge on the role of environmental attributes in the experience of hospitality. Besides Brotherton (2005), who showed that modern, clean, comfortable and bright are aspects people associate with hospitality, little is known about how the perception of attributes of the physical service environment contribute to our experience of hospitality. Research has shown that the experience of hospitality in service environments is represented by three factors: inviting, care and comfort (Pijls, Groen, Galetzka & Pruyn, 2017). These factors are expected to be triggered by mental concepts grounded in bodily sensations. According to embodied cognition theory, attributes we perceive with our senses result in bodily sensation, such as warmth, weight or distance, which in turn affect our mental state. Embodied cognition is the idea that emotions and thoughts not only originate in the brain, but that we also think and feel with our body (Lobel, 2014). We expect that embodied cognition is one of the mechanisms underlying the experience of hospitality, linking the experience of hospitality to the impact of the physical environment. As far as we know the theory of embodied cognition has not yet been studied in the context of hospitality. Mental warmth is one of the abstract metaphors grounded in a concrete experience, in this case in the sensation of physical warmth (Williams & Bargh, 2008; Lakoff and Johnson, 1999). This experiment explores the effect of the perceived physical warmth on the experience of mental warmth among customers of a theatre by examining the effect of cold versus warm furniture material and by examining the effect of cold versus hot drinks. Based on the studies performed by Williams and Bargh (2008) and IJzerman & Semin (2009) on the effect of holding cold versus hot drinks, it is expected that: H1 Touching and drinking a hot drink will lead to the experience of hospitality H2 Touching and drinking a hot drink will lead to the experience of physical warmth, and subsequently mental warmth, which will result an increased experience of hospitality, compared to touching and drinking a cold drink. H3 Sitting on furniture made of warm material will lead to the experience of hospitality H4 Sitting on furniture made of warm material will lead to the experience of physical warmth, and subsequently mental warmth, which will result an increased experience of hospitality, compared to touching and drinking a cold drink. The experience of hospitality will be measured in a theatre foyer. A 3 (warm versus neutral versus cold furniture material) x 2 (warm versus cold drink) between-subjects factorial design will be employed. Visitors to the theatre will be asked to fill in the survey, while holding and drinking either a warm or a cold drink, and while sitting either on warm, neutral or cold furniture. The experience of hospitality will be measured with the 13-item Experience of Hospitality Scale. Mental warmth will be measured by 5 questions, such as ‘the foyer has an intimate atmosphere’, ‘I’m warmly treated in this theatre’, ‘this theatre is a warm organisation’. Results are forthcoming

Cluster Masses Accounting for Structure along the Line of Sight

Weak gravitational lensing of background galaxies by foreground clusters offers an excellent opportunity to measure cluster masses directly without using gas as a probe. One source of noise which seems difficult to avoid is large scale structure along the line of sight. Here I show that, by using standard map-making techniques, one can minimize the deleterious effects of this noise. The resulting uncertainties on cluster masses are significantly smaller than when large scale structure is not properly accounted for, although still larger than if it was absent altogether.Comment: 5 pages, 5 figure

XMM-Newton X-ray and HST weak gravitational lensing study of the extremely X-ray luminous galaxy cluster Cl J120958.9+495352 (z = 0.902)

Large scale structure and cosmolog