This psychophysiological study is the first to examine the relationship between emotional tears and emotional piloerection (i.e., goosebumps). Although both phenomena have been related to peak states of being moved, details about their temporal occurrence and the associated levels of physiological arousal have remained unknown. In our study, we used emotionally powerful film scenes that were self-selected by participants. Our findings show that even within peak moments of emotional arousal, a gradation of intensity is possible. The overlap of tears and goosebumps signifies a maximal climax within peak moments. On the side of the stimulus, we found that displays of prosocial behavior play a crucial role in the elicitation of tears and goosebumps. Finally, based on the results of a formal film analysis of the tears-eliciting clips provided by our participants, as compared to randomly extracted, equally long control clips from the same films, we show how the technical and artistic making of the clips was optimized for the display of social interaction and emotional expressions.

Positioned AlGaAs nanowires with an embedded axial heterostructure GaAs quantum dot (QD) on a prepatterned substrate have been grown. The geometry of the nanowires allows for an outcoupling of the emitted light through the nanowire tip and thereby to probe a single nanowire directly on the growth substrate. Single QD linewidths as small as 95 μeV and photon antibunching were observed at continuous wave laser excitation with a second order autocorrelation function g(2)(0)=0.46. The results represent an attractive bottom-up fabrication approach for the realization of high efficiency photonic wire based single photon sources.

We present a polarization-independent metamaterial design for the construction of electrically tunable terahertz (THz) devices. The implemented structure consists of an array of gold crosses fabricated on top of an n-doped gallium arsenide (GaAs) layer. Utilizing THz time-domain spectroscopy, we show that the electric resonance and thus the transmission properties of the cross structure can be tuned by an externally applied bias voltage. We further demonstrate the fast amplitude modulation of a propagating THz wave for modulation frequencies up to 100 kHz.

Room temperature (RT) memory operation of a single InAs quantum dot (QD) layer serving as floating gate is demonstrated. In an in-plane gated quantum-wire transistor, the charge state of the self-assembled InAs QDs is controlled by the applied gate voltage. Due to the floating-gate function of the QDs on a nearby transport channel, threshold hysteresis exceeding 200mV and storage times of several minutes are observed. The RT operation is attributed to an optimized positioning of the QDs at the site of a local minimum in the AlGaAs conduction band.

The authors report on tunable, miniaturized, two-segment coupled cavity quantum cascade lasers fabricated in a process with a single dry etch step. They observed controllable vernier-effect-based mode switching, induced by the spectral shift of the short cavity’s Fabry-Pérot mode comb due to Joule heating. With the help of this discontinuous tuning mechanism, single-mode operation with routinely ∼20dB side mode suppression ratio was achieved over a broad spectral range. The authors measured a quasicontinuous tuning range of 12cm−1 (138nm) and an entire single-mode tuning range of 16.5cm−1 (190nm), centered around 933cm−1 (10.7μm).