AC-Conductance through an Interacting Quantum Dot

We investigate the linear ac-conductance for tunneling through an arbitrary interacting quantum dot in the presence of a finite dc-bias. In analogy to the well-known Meir-Wingreen formula for the dc case, we are able to derive a general formula for the ac-conductance. It can be expressed entirely in terms of local correlations on the quantum dot, in the form of a Keldysh block diagram with four external legs. We illustrate the use of this formula as a starting point for diagrammatic calculations by considering the ac-conductance of the noninteracting resonant level model and deriving the result for the lowest order of electron-phonon coupling. We show how known results are recovered in the appropriate limits.Comment: 4+ pages, 4 figure

Controlled Dephasing of Electrons by Non-Gaussian Shot Noise

In a 'controlled dephasing' experiment [1-3], an interferometer loses its coherence due to entanglement with a controlled quantum system ('which path' detector). In experiments that were conducted thus far in mesoscopic systems only partial dephasing was achieved. This was due to weak interactions between many detector electrons and the interfering electron, resulting in a Gaussian phase randomizing process [4-10]. Here, we report the opposite extreme: a complete destruction of the interference via strong phase randomization only by a few electrons in the detector. The realization was based on interfering edge channels (in the integer quantum Hall effect regime, filling factor 2) in a Mach-Zehnder electronic interferometer, with an inner edge channel serving as a detector. Unexpectedly, the visibility quenched in a periodic lobe-type form as the detector current increased; namely, it periodically decreased as the detector current, and thus the detector's efficiency, increased. Moreover, the visibility had a V-shape dependence on the partitioning of the detector current, and not the expected dependence on the second moment of the shot noise, T(1-T), with T the partitioning. We ascribe these unexpected features to the strong detector-interferometer coupling, allowing only 1-3 electrons in the detector to fully dephase the interfering electron. Consequently, in this work we explored the non-Gaussian nature of noise [11], namely, the direct effect of the shot noise full counting statistics [12-15].Comment: 14 pages, 4 figure

Open, Small-scale Fabrication: A Catalyst for Educating Communities about the Creation of Products

We introduce an experimental platform called Project Provenance that connects small-scale makers with people in their local community to share information about the products they make. The findings from a series of interviews with both digital fabricators and more traditional craftsmen are presented. A strong desire to promulgate ‘making stories’ was discovered. This paper also explores associated technologies, particularly product supply chain transparency through open linked data. There is potential for promoting small-scale urban fabrication, made increasingly viable through digital methods, by connecting makers with people in their cities. This could enable ‘making education’ at all ages, employment and empathetic connections within different sectors of local communities

How embodied interactions manifest themselves during collaborative learning in classroom settings

New physical computing toolkits offer much promise for promoting collaborative learning by engendering embodied interactions that can support collaborative discovery. To examine how these can unfold during a learning activity, we conducted a classroom study where pairs of children explored mappings between various sensors and actuators embedded in a physical-digital artifact. We found how a number of embodied interactions emerged that were effectively used to progress learning through the processes of showing, sharing and contestin

Data in the garden: a framework for exploring provocative prototypes as part of research in the wild

Research in the Wild (RITW) typically involves the deployment of technology in a setting, using the methodology of ‘probing’ contexts, to change behaviour or enhance community practice. This way of conducting HCI research is becoming an increasingly popular approach. To help in this endeavour, Rogers and Marshall [28] present an overarching framework that considers the different aspects involved. As part of the framework, they stress the importance of the design of the technology to be deployed. However, they do not detail how researchers should go about this. Here, we propose how to fill this gap: by providing a more explicit and principled rationale as part of RITW, presenting a method for accomplishing this, and reporting a case study about community gardening that uses a provocative prototype

Make or Shake: An Empirical Study of the Value of Making in Learning about Computing Technology

Learning about computing technology has become an increasingly important part of the school curriculum but it remains unclear how best to teach it to children. Here, we report on an empirical study that investigated how the process of making affects how children of different ages learn about computing technology. In one condition, they had to first make an electronic cube before conducting other activities and in the other they were given a ready made one to use. The results of the study show that for younger children, the making significantly improved their performance in a post-lesson test, whereas the older children performed equally well in both conditions. We discuss possible reasons for this, in terms of differences in creative appropriation. We also saw much spontaneous collaboration between the children that suggests making can encourage a collaborative relationship between children of different ages

ConnectUs: A New Toolkit for Teaching about the Internet of Things

The emerging Internet of Things (IoT), through which vast amounts of everyday objects are becoming embedded with computing and networking capabilities, is rapidly changing the way society uses and experiences technology. Despite this, children do not systematically learn about IoT in schools. This demonstration will showcase ConnectUs, a new IoT toolkit, which can be used to introduce children to a variety of IoT concepts, and provide users with the opportunity to design their own IoT system

Democratizing children's engagement with the internet of things through connectus

The emerging Internet of Things (IoT), through which billions of everyday objects are becoming embedded with the abilities to sense their environment, compute data, and wirelessly connect to other devices, has been widely recognized as the new disruptive technology of our time. The predicted ubiquity of connected devices indicates that IoT technologies are quickly becoming an important part of the digital fluency curriculum, however, no research yet exists on suitable pedagogical approaches for teaching children about the IoT. The current research explores the design and deployment of a pedagogical approach and associated tangible toolkit, ConnectUs, that will enable 10-13 year old children to explore and design for the Internet of Things

CurationSpace: Cross-Device Content Curation Using Instrumental Interaction

For digital content curation of historical artefacts, curators collaboratively collect, analyze and edit documents, images, and other digital resources in order to display and share new representations of that information to an audience. Despite their increasing reliance on digital documents and tools, current technologies provide little support for these specific collaborative content curation activities. We introduce CurationSpace – a novel cross-device system – to provide more expressive tools for curating and composing digital historical artefacts. Based on the concept of Instrumental Interaction, CurationSpace allows users to interact with digital curation artefacts on shared interactive surfaces using personal smartwatches as selectors for instruments or modifiers (applied to either the whole curation space, individual documents, or fragments). We introduce a range of novel interaction techniques that allow individuals or groups of curators to more easily create, navigate and share resources during content curation. We report insights from our user study about people’s use of instruments and modifiers for curation activities

MakeMe, codeme, connectus: Learning digital fluency through tangible magic cubes

Recent years have seen an increased empirical interest in designing new approaches to teaching digital fluency to wide audiences. Tangible physical computing interfaces provide much scope for teaching abstract digital fluency concepts in an engaging and playful way. However, questions remain as to how both the form factor and the corresponding task types of such interfaces can be best designed to support learning. In this hands-on workshop, participants will explore how digital fluency topics might be taught through making, discovery learning and coding by interacting with the tangible Magic Cubes toolkit (Figure 1). The workshop will culminate in a discussion of how tangible toolkits for learning can be better designed to encourage collaborative and engaging learning experiences