83 research outputs found
State Transfer in Permanently Coupled Quantum Chains
No full textin Quantum Information Processing From Theory to Experiment Vol. 199, NATO Science Series: Computer & Systems Sciences; Edited by: D.G. Angelakis, M. Christandl, A. Ekert, A. Kay and S. Kulik (Proceedings of the NATO Advanced Research Workshop, Crete.
Out-of-equilibrium physics in driven dissipative coupled resonator arrays
No full textCoupled resonator arrays have been shown to exhibit interesting many- body physics including Mott and Fractional Hall states of photons. One of the main differences between these photonic quantum simulators and their cold atoms coun- terparts is in the dissipative nature of their photonic excitations. The natural equi- librium state is where there are no photons left in the cavity. Pumping the system with external drives is therefore necessary to compensate for the losses and realise non-trivial states. The external driving here can easily be tuned to be incoherent, coherent or fully quantum, opening the road for exploration of many body regimes beyond the reach of other approaches. In this chapter, we review some of the physics arising in driven dissipative coupled resonator arrays including photon fermionisa- tion, crystallisation, as well as photonic quantum Hall physics out of equilibrium. We start by briefly describing possible experimental candidates to realise coupled resonator arrays along with the two theoretical models that capture their physics, the Jaynes-Cummings-Hubbard and Bose-Hubbard Hamiltonians. A brief review of the analytical and sophisticated numerical methods required to tackle these systems is included
Services Marketing in a Cross-Cultural Environment: Elekta in Germany
No full textAbstract Title: Services Marketing in a Cross-Cultural Environment: Elekta in Germany Level: Master Thesis in Business Administration Author: Katrina Dietrich & Giorgos Angelakis Supervisor: Maria Fregidou-Malama Examiner: Akmal Hyder Date: 2014-January Aim: This study aims to examine how culture, trust, network and standardization/adaption are applied within the Service Marketing of Elekta in Germany and if they overcome the characteristics of Services within a culturally different environment. Method: The research uses qualitative data, applies a single case study, questionnaires and semi-structured interviews to collect primary data. Result & Conclusions: The applied model shows that Elekta uses a balance between adaptation and standardization as well as applies trust and network under awareness and use of the German culture. These factors are used in combination and are influencing each other in order to create a homogeneous and tangible service. Suggestions for future research: The case study indicates that one company is subject of the study in one country, hence generalization cannot be achieved. Therefore future research of other countries and other service industries can extend this research. Contribution of the thesis: This research stresses the importance of culture, adaptation/ standardisation and trust and networks in cross-cultural services marketing of Elekta. It shows how heterogeneity and intangibility are influenced by the variable trust, network, adaptation/ standardization and culture.
Heritage data-centric research: are FAIR data fair enough?
No full textIn the current trend for e-Science, i.e. collaborative, computationally- or data-intensive research, archaeology is not a laggard. A number of initiatives are addressing how to manage and use data produced by heritage research, most notably the ARIADNE one in the archaeological domain (https://www.ariadne-infrastructure.eu), presently involving the most important research centres from all European countries in creating a comprehensive and integrated archaeological data infrastructure that so far has already registered little less than 2.000.000 archaeological datasets. Such infrastructure, implemented by ARIADNE, is bringing archaeology out of the “long tail of science”, i.e. those disciplines that make little use of data-centric research. It is revolutionising the concept of Big Data: not relatively few datasets, each with terabytes of numbers, as in nuclear physics; but millions of small datasets, all potentially relevant to a specific research question but including a large (and unknown) majority probably irrelevant at all. E-Science relies on the well-known FAIR principles (https://www.force11.org/fairprinciples), stating that data should be Findable, Accessible, Interoperable and Re-usable. Now, if “F”, “A” and “I” mainly depend on the technical way in which data and metadata are generated, stored, managed and curated, the “R” has less technical (but not less important) implications. It involves theoretical, methodological and epistemological aspects that have not received enough attention in the current debate. It has been argued that e-science discovery could be modelled as a deterministic discovery process; nevertheless, even in this perspective, simply modelling the provenance of data is not sufficient, but the provenance of the hypotheses and results generated from analyzing the data need to be modelled as well. Thus, to reuse data in cultural heritage it is necessary to expand the “R” facet of the FAIR principles at least into R3: Re-usable, Relevant and Reliable. Judging relevance and reliability may appear obvious to a human eye, but it is not to machine processing. Data reliability depends on a chain of trust that needs to be adequately supported by documentation, and on this regard the CIDOC CRM may play a key role. If in the past reference to previous discoveries published in journals and books was based on the academic practice of peer-review and on the authoritativeness of the author and of the publication, re-using data created by others is still lacking a similar good practice.The session will discuss such aspects and propose ways to address the issue. Contributions will come from purely cultural heritage practice (“What would you need to rely on somebody else’s data?”) to semantics (“What would you suggest to document, in order to support reliability?”). Both aspects will be analysed in light of the CRM: does it already provide a sufficiently rich toolbox, or additions are required? If so, which ones
Quantum simulations with photons and polaritons: merging quantum optics with condensed matter physics
No full textThis book reviews progress towards quantum simulators based on photonic and hybrid light-matter systems, covering theoretical proposals and recent experimental work. Quantum simulators are specially designed quantum computers. Their main aim is to simulate and understand complex and inaccessible quantum many-body phenomena found or predicted in condensed matter physics, materials science and exotic quantum field theories. Applications will include the engineering of smart materials, robust optical or electronic circuits, deciphering quantum chemistry and even the design of drugs. Technological developments in the fields of interfacing light and matter, especially in many-body quantum optics, have motivated recent proposals for quantum simulators based on strongly correlated photons and polaritons generated in hybrid light-matter systems. The latter have complementary strengths to cold atom and ion based simulators and they can probe for example out of equilibrium phenomena in a natural driven-dissipative setting. This book covers some of the most important works in this area reviewing the proposal for Mott transitions and Luttinger liquid physics with light, to simulating interacting relativistic theories, topological insulators and gauge field physics. The stage of the field now is at a point where on top of the numerous theory proposals; experiments are also reported. Connecting to the theory proposals presented in the chapters, the main experimental quantum technology platforms developed from groups worldwide to realize photonic and polaritonic simulators in the laboratory are also discussed. These include coupled microwave resonator arrays in superconducting circuits, semiconductor based polariton systems, and integrated quantum photonic chips. This is the first book dedicated to photonic approaches to quantum simulation, reviewing the fundamentals for the researcher new to the field, and providing a complete reference for the graduate student starting or already undergoing PhD studies in this area
Topological data analysis and machine learning
No full textTopological data analysis refers to approaches for systematically and
reliably computing abstract ``shapes'' of complex data sets. There are various
applications of topological data analysis in life and data sciences, with
growing interest among physicists. We present a concise yet (we hope)
comprehensive review of applications of topological data analysis to physics
and machine learning problems in physics including the detection of phase
transitions. We finish with a preview of anticipated directions for future
research.Comment: Invited review, 15 pages, 7 figures, 117 reference
Revitalization of the Greek Vitis database ::a multimedia web-backed genetic database for germplasm management of Vitis resources in Greece
No full textLefort and Roubelakis-Angelakis ([2000. The Greek Vitis Database: A multimedia web-backed genetic database for germplasm management of Vitis resources in Greece. Journal of Wine Research, 11(3), 233–242. https://doi.org/10.1080/713684241)] were the first to develop a Greek Vitis multimedia web-backed service at the Laboratory of Plant Physiology and Biotechnology of the University of Crete 20 years ago. This service was named Greek Vitis Database (GVD) and it provided free access to six databases, gathering information about Greek cultivars of Vitis vinifera: an information database; a nuclear single sequence repeats (nSSR) microsatellite profiles database; a chloroplast microsatellite (cpSSR) database; a combined nSSR – cpSSR profiles database; an ampelographic database; and a rootstock database. Information and descriptive images were combined with SSR profiles. Although simple sequence repeats are still the markers of choice for compilation, standardization and exchange of information regarding grapevine genetic resources, the advances in computing technology through the years made the GDV inactive. This report is to announce the renovation and revitalization of GVD using new computing technologies. The GVD can now be accessible at http://greekvitisdb.biology.uoc.gr or in the previous address http://www.biology.uoc.gr/gvd redirected
Sustainability of underground hydro-technologies: From ancient to modern times and toward the future
No full textAn underground aqueduct is usually a canal built in the subsurface to transfer water from a starting point to a distant location. Systems of underground aqueducts have been applied by ancient civilizations to manage different aspects of water supply. This research reviews underground aqueducts from the prehistoric period to modern times to assess the potential of achieving sustainable development of water distribution in the sectors of agriculture and urban management, and provides valuable insights into various types of ancient underground systems and tunnels. The review illustrates how these old structures are a testament of ancient people’s ability to manage water resources using sustainable tools such as aqueducts, where the functionality works by using, besides gravity, only “natural” engineering tools like inverted siphons. The study sheds new light on human’s capability to collect and use water in the past. In addition, it critically analyzes numerous examples of ancient/historic/pre-industrial underground water supply systems that appear to have remained sustainable up until recent times. The sustainability of several underground structures is examined, correlated to their sound construction and regular maintenance. Moreover, several lessons can be learned from the analysis of ancient hydraulic works, particularly now, as many periodically hydrologic crises have occurred recently, overwhelmingly impacted by climate change and/or over-exploitation and degradation of available water resources.Teachers of Practice /
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