Characterizing creative scientists in nano S & T : productivity, multidisciplinarity, and network brokerage in a longitudinal perspective

While some believe that publication and citation scores are key predictors of breakthroughs in science, others claim that people who work at the intersection of scientific communities are more likely to be familiar with selecting and synthesizing alternatives into novel ideas. This paper contributes to this controversy by presenting a longitudinal comparison of highly creative scientists with equally productive researchers. The sample of creative scientists is identified by combining information on science awards and nominations by international peers covering research accomplishments in the mid-1990s. Results suggest that it is not only the sheer quantity of publications that causes scientists to produce creative pieces of work. Rather, their ability to effectively communicate with otherwise disconnected peers and to address a broader work spectrum also enhances their chances to be widely cited and to develop novel ideas. --

Diffusion of Monochromatic Classical Waves

We study the diffusion of monochromatic classical waves in a disordered acoustic medium by scattering theory. In order to avoid artifacts associated with mathematical point scatterers, we model the randomness by small but finite insertions. We derive expressions for the configuration-averaged energy flux, energy density, and intensity for one, two and three dimensional (1D, 2D and 3D) systems with an embedded monochromatic source using the ladder approximation to the Bethe-Salpeter equation. We study the transition from ballistic to diffusive wave propagation and obtain results for the frequency-dependence of the medium properties such as mean free path and diffusion coefficient as a function of the scattering parameters. We discover characteristic differences of the diffusion in 2D as compared to the conventional 3D case, such as an explicit dependence of the energy flux on the mean free path and quite different expressions for the effective transport velocity.Comment: 11 pages, 2 figure

Charge Density Wave Ratchet

We propose to operate a locally-gated charge density wave as an electron pump. Applying an oscillating gate potential with frequency $f$ causes equally spaced plateaux in the sliding charge density wave current separated by $\Delta I=2eNf,$ where $N$ is the number of parallel chains. The effects of thermal noise are investigated.Comment: To be published in Applied Physics Letter

The Long Run Consequences of Unilateral Divorce Laws on Children –Evidence from SHARELIFE

Previous research has shown adverse effects of growing up under unilateral divorce laws on long-term outcomes of children. It remains an open question of whether long-term effects of early childhood conditions arise because divorce laws raise the likelihood of parental marital disruption, or whether unilateral divorce laws also affect children in intact marriages by changing intra-household bargaining. Using newly available data from SHARELIFE for eleven Western European countries we address this question employing a differences-in-differences approach and controlling for childhood family structure and socioeconomic status. Like previous research, we find strong adverse effects of growing up under unilateral divorce laws on the well-being of children, and this effect remains even when controlling for childhood variables. We conclude that unilateral divorce laws affect children by changing family bargaining in intact marriages.

Feedback control of noise in spin valves by the spin-transfer torque

The miniaturisation of magnetic read heads and random access memory elements makes them vulnerable to thermal fluctuations. We demonstrate how current-induced spin-transfer torques can be used to suppress the effects of thermal fluctuations. This enhances the fidelity of perpendicular magnetic spin valves. The simplest realization is a dc current to stabilize the free magnetic layers. The power can be significantly reduced without losing fidelity by simple control schemes, in which the stabilizing current-induced spin-transfer torque is controlled by the instantaneous resistance.Comment: 4pages, 2 figure