Observation of narrow Autler-Townes components in the resonant response of a dense atomic gas

We have experimentally studied the reflection of a weak probe beam from a dense atomic potassium vapor in the presence of a strong laser field tuned to the atomic resonance transition. We have observed an Autler-Townes doublet under hitherto unexplored conditions, namely that the Rabi frequency induced by the strong laser field is much smaller than the self-broadened width of the resonance transition of the unexcited vapor. We attribute our observation to a reduction of the atomic decoherence by the strong drive field. We present a theoretical model of nonlinear processes in a dense atomic gas to explain the observed results

Comics Telling Refugee Stories

This chapter begins with an indicative survey of comics responding to the current ‘refugee crisis’. The comics in question adopt one of two distinct and established approaches. The first is reportage, usually featuring the author/creator as a central device, while the second re-works and renders testimony in visual form. In their different ways, both contribute to a wider repertoire of positive and sympathetic representations of refugees, offering a counter-point to hostile media and political discourse, often by a focus on the stories of individuals. Mobilizing compassion and moral responses through personal stories of hardship, trauma, tenacity, and survival has long been a tactic of reformist agendas and humanitarian advocacy. By their qualitative difference from dominant forms of factual discourse, comics offer certain advantages. They may also circumvent certain problems associated with photographic representations of suffering. Such comics can nevertheless run the risk of re-producing established victim tropes, and just as with other forms of representation, human-interest angles carry the potential to obscure political dimensions. In an attempt to consider and situate these concerns, the analysis considers the various positions and relations that constitute ‘refugee comics’: subjects, readers, creators, (im)materiality, and circulation

Inflation Dynamics and the Cost Channel of Monetary Transmission

Evidence from vector autoregressions indicates that the impact of interest rate shocks on macroeconomic aggregates can substantially be affected by the so-called cost channel of monetary transmission. In this paper, we apply a structural approach to examine the relevance of the cost channel for inflation dynamics in G7 countries. Since firms' costs of working capital increase with interest rates, we augment a (hybrid) New Keynesian Phillips curve by including the short-run nominal interest rate. We find significant and varying direct interest rate effects for the majority of countries, including member countries of the EMU. Simulations further demonstrate that the estimated interest rate coefficients can substantially affect inflation responses to monetary policy shocks, and can even lead to inverse inflation responses, when the cost channel is - relative to the demand channel - sufficiently strong

An Efficient Scheme for Broadband Adaptive Beamforming

This paper introduces an oversampled subband approach to linearly constrained minimum variance adaptive broadband beamforming. This method is motivated by the considerable reduction in computation over fullband implementation and resulting large computational complexity when fullband beamformers with high spatial and spectral resolution are required. We present the proposed subband adaptive beamformer structure, discuss advantages and limitations of it, and comment on the correct projection of the constraints in the subband domain. In a simulation, the proposed subband structure is compared to a fullband adaptive beamformer, highlighting the benefit of our method

An Efficient Scheme for Broadband Adaptive Beamforming

This paper introduces an oversampled subband approach to linearly constrained minimum variance adaptive broadband beamforming. This method is motivated by the considerable reduction in computation over fullband implementation and resulting large computational complexity when fullband beamformers with high spatial and spectral resolution are required. We present the proposed subband adaptive beamformer structure, discuss advantages and limitations of it, and comment on the correct projection of the constraints in the subband domain. In a simulation, the proposed subband structure is compared to a fullband adaptive beamformer, highlighting the benefit of our method