2,483 research outputs found
Spending time with money: from shared values to social connectivity
This article has been made available through the Brunel Open Access Publishing Fund.There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions
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
United States Regulation of Stem Cell Research: Recasting Government\u27s Role and Questions to Be Resolved
This article directly addresses the stem cell controversy, but also the broader history and norms regarding the roles of federal and state government in U.S. science research funding
Magnetization dynamics and Gilbert damping in ultrathin Co48Fe32B20 films with out-of-plane anisotropy
Time resolved magneto-optical Kerr measurements are carried out to study the precessional dynamics of ferromagnetic thin films with out-of-plane anisotropy. A combined analysis of parameters, such as coercive fields, magnetic anisotropy, and Gilbert damping a, is reported. Using a macrospin approximation and the Landau-Lifshitz-Gilbert equation, the effective anisotropy and a are obtained. A large damping varying with the applied field as well as with the thickness of the ferromagnetic layer is reported. Simulations using a distribution in the effective anisotropy allow us to reproduce the field evolution of a. Moreover, its thickness dependence correlates with the spin pumping effect. © 2009 American Institute of Physics
All-optical control of ferromagnetic thin films and nanostructures
The interplay of light and magnetism has been a topic of interest since the
original observations of Faraday and Kerr where magnetic materials affect the
light polarization. While these effects have historically been exploited to use
light as a probe of magnetic materials there is increasing research on using
polarized light to alter or manipulate magnetism. For instance deterministic
magnetic switching without any applied magnetic fields using laser pulses of
the circular polarized light has been observed for specific ferrimagnetic
materials. Here we demonstrate, for the first time, optical control of
ferromagnetic materials ranging from magnetic thin films to multilayers and
even granular films being explored for ultra-high-density magnetic recording.
Our finding shows that optical control of magnetic materials is a much more
general phenomenon than previously assumed. These results challenge the current
theoretical understanding and will have a major impact on data memory and
storage industries via the integration of optical control of ferromagnetic
bits.Comment: 21 pages, 11 figure
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