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We identified quasiparticle states at well-defined energies inside the superconducting gap of the electron system at the LaAlO$_3$-SrTiO$_3$ interface using tunneling spectroscopy. The states are found only in a number of samples and depend upon the thermal-cycling history of the samples. The states consist of a peak at zero energy and other peaks at finite energies, symmetrically placed around zero energy. These peaks disappear, together with the superconducting gap, with increasing temperature and magnetic field. We discuss the likelihood of various physical mechanisms that are known to cause in-gap states in superconductors and conclude that none of these mechanisms can easily explain the results. The conceivable scenarios are the formation of Majorana bound states, Andreev bound states, or the presence of an odd-frequency spin triplet component in the superconducting order parameter., Comment: 11 pages, 5 figures

Anthropomimetic robots are robots that sense, behave, interact and feel like humans. By this definition, anthropomimetic robots require human-like physical hardware and actuation, but also brain-like control and sensing. The most self-evident realization to meet those requirements would be a human-like musculoskeletal robot with a brain-like neural controller. While both musculoskeletal robotic hardware and neural control software have existed for decades, a scalable approach that could be used to build and control an anthropomimetic human-scale robot has not been demonstrated yet. Combining Myorobotics, a framework for musculoskeletal robot development, with SpiNNaker, a neuromorphic computing platform, we present the proof-of-principle of a system that can scale to dozens of neurally-controlled, physically compliant joints. At its core, it implements a closed-loop cerebellar model which provides real-time low-level neural control at minimal power consumption and maximal extensibility: higher-order (e.g., cortical) neural networks and neuromorphic sensors like silicon-retinae or -cochleae can naturally be incorporated., Comment: Accepted at IEEE Robotics and Automation Magazine on 2015-12-31

The superconductor at the LaAlO3-SrTiO3 interface provides a model system for the study of two-dimensional superconductivity in the dilute carrier density limit. Here we experimentally address the pairing mechanism in this superconductor. We extract the electron-phonon spectral function from tunneling spectra and conclude, without ruling out contributions of further pairing channels, that electron-phonon mediated pairing is strong enough to account for the superconducting critical temperatures. Furthermore, we discuss the electron-phonon coupling in relation to the superconducting phase diagram. The electron-phonon spectral function is independent of the carrier density, except for a small part of the phase diagram in the underdoped region. The tunneling measurements reveal that the increase of the chemical potential with increasing carrier density levels off and is zero in the overdoped region of the phase diagram. This indicates that the additionally induced carriers do not populate the band that hosts the superconducting state and that the superconducting order parameter therefore is weakened by the presence of charge carriers in another band.

The ability to control materials properties through interface engineering is demonstrated by the appearance of conductivity at the interface of certain insulators, most famously the {001} interface of the band insulators LaAlO$_{3}$ and TiO$_{2}$-terminated SrTiO$_{3}$ (STO). Transport and other measurements in this system show a plethora of diverse physical phenomena. To better understand the interface conductivity, we used scanning superconducting quantum interference device microscopy to image the magnetic field locally generated by current in an interface. At low temperature, we found that the current flowed in conductive narrow paths oriented along the crystallographic axes, embedded in a less conductive background. The configuration of these paths changed on thermal cycling above the STO cubic-to-tetragonal structural transition temperature, implying that the local conductivity is strongly modified by the STO tetragonal domain structure. The interplay between substrate domains and the interface provides an additional mechanism for understanding and controlling the behaviour of heterostructures.

One of the central goals of the KP-Lab project is to co-design pedagogical methods and technologies for knowledge creation and practice transformation in an integrative and reciprocal manner. In order to facilitate this process user tasks, driving objectives and high-level requirements have been introduced as conceptual tools to mediate between technological design empirical research as well as theory development. The user tasks describe the generic activities users should be able to perform interactively with KP-Lab technology, based on the perspective of trialogical learning. The driving objectives are derived from the KP-Lab design principles of trialogical learning, the results obtained from empirical investigations that were performed in the pedagogical work packages as well as the reviews and analyses of available technologies and their potentials carried out by technical partners. In short, the driving objectives provide overall scope and direction for the technology development based on KP-Lab theory and practice. They encapsulate the high-level requirements which provide more detailed descriptions of technology support for supporting knowledge creation and practice transformation. This deliverable provides an updated overview of driving objectives and high-level requirements for guiding the technological design and implementation of the KP-Lab system. The document highlights also particularly the added value of semantic services from a user's point of view as well as the use of respective applications in different research cases. This document supersedes the current list of driving objectives and high-level requirements as documented in DoW3.1 (KP-Lab, 2008b). The document is focused on the description of user tasks, driving objectives and high-level requirements. An in depth discussion of the objectives and requirements from a theoretical, pedagogical and technological perspective is beyond the scope of this document. For respective accounts the reader is referred to D3.3 (KP-lab, 2008c), the reports on empirical studies carried out by WP8-10 as well as the technical specifications provided by WP4-6. (Contains 24 tables, 2 figures, and 3 footnotes.