Effects of Raman scattering and attenuation in silica fiber-based parametric frequency conversion

Four-wave mixing in the form of Bragg scattering (BS) has been predicted to enable quantum noise less frequency conversion by analytic quantum approaches. Using a semi-classical description of quantum noise that accounts for loss and stimulated and spontaneous Raman scattering, which are not currently described in existing quantum approaches, we quantify the impacts of these effects on the conversion efficiency and on the quantum noise properties of BS in terms of an induced noise figure (NF). We give an approximate closed-form expression for the BS conversion efficiency that includes loss and stimulated Raman scattering, and we derive explicit expressions for the Raman-induced NF from the semi-classical approach used here.Comment: 14 single col pages, 11 figure

LSS, a problem solving skill for graduates and SMEs: Case Study of investigation in a UK Business School curriculum

Purpose - This research aims to investigate the feasibility of a systematic Lean Six Sigma (LSS) education through the curriculum of business schools to respond to the existing gap between the graduate’s expectation of employability and skill requirements by the Small and Medium Sized Enterprises (SMEs). Design/approach/methodology - One UK business school has been used as a case study to conduct an extensive module and programme review followed by a semi-structured interview with the potentially suitable core and programme-specific module leaders and also the comparative Analysis between content of these modules and the existing LSS high-street training themes. Findings – The result revealed a high potential of the existing modules in the business schools equivalent to the private sector training providers to increase the level of LSS problem solving knowledge and skill for all graduates and improve their employability and productivity for the SMEs. Practical implications/limitations – This research has been carried out in a single UK–based Business School through a qualitative approach. A further in-depth analysis in a broader scale is required to investigate the practical implications in a better way. Originality/Value – The result of this study highlights the role of LSS to reduce the knowledge and skill gap between the business schools as the source of the explicit knowledge, graduates as the knowledge and skill bearer, and SMEs as the knowledge and skill users

Vores sikkerhed og verdens udvikling. Sikkerhed, bistand og begrebsforandring mellem Danmark og FN

Our Security and Global Development: Security, Aid, and Conceptual Change between Denmark and the United NationsThis article investigates the diffusion and translation of the so-called ‘security-development nexus’ and its forerunners in Denmark. In doing so, it calls for a conceptual and transnational perspective in investigating national adaptations of global concepts and agendas and vice versa. Through a focus on changing political concepts, this article argues that a more thorough understanding of the transnational and entangled dynamics of both national and global policy change may be reached. Illustratively, it is found that Danish security/development discourse and practice was driven by the previously unrecognized interlinkages and confluences between a (changing) national policy ‘tradition’ and a long-term pattern of conceptual change within the UN and other international institutions

Spectrally pure heralded single photons by spontaneous four-wave mixing in a fiber: reducing impact of dispersion fluctuations

We model the spectral quantum-mechanical purity of heralded single photons from a photon-pair source based on nondegenerate spontaneous four-wave mixing taking the impact of distributed dispersion fluctuations into account. The considered photon-pair-generation scheme utilizes pump-pulse walk-off to produce pure heralded photons and phase matching is achieved through the dispersion properties of distinct spatial modes in a few-mode silica step-index fiber. We show that fiber-core-radius fluctuations in general severely impact the single-photon purity. Furthermore, by optimizing the fiber design we show that generation of single photons with very high spectral purity is feasible even in the presence of large core-radius fluctuations. At the same time, contamination from spontaneous Raman scattering is greatly mitigated by separating the single-photon frequency by more than 32 THz from the pump frequency

Towards Relational Leadership In the Cultural Sector

The thesis is an inquiry into how leadership is performed narratively in the cultural sector. Chapter 1 draws the cultural sector as a narrative landscape, and the reader is invited on a tour around this narrative landscape as seen through the eyes of some of the top guns in the cultural sector. Seen from this vantage, leadership in the cultural sector seems to be predominantly performed by relating narratives with reference to the metanarrative of the Enlightenment. The inquiry, however, draws on Lyotard (1984) to argue that such extralinguistic legitimization is in a crisis of legitimacy, wherefore the inquiry embarks on a problematization of the dominant understanding of leadership in the cultural sector with the activist aspiration of suggesting a postmoderning understanding of leadership in the cultural sector being performatively legitimized. Chapter 2 argues in favor of a relational, non-entitative understanding of narratives and it points to emplotment as a process of finding the best fit. This relational understanding of narratives allows the project to inquire into leadership performed narratively in all kinds of empirical settings, not confining itself to formal leadership contexts. Chapter 3 offers a genealogic approach to what the project has defined as the dominant narrative in the cultural sector, the narrative of art for art’s sake (the AFAS narrative), which the project argues function as an implicit standard. This includes notions of aesthetic autonomy such as suggested by Kant in 1790, artistic freedom and art for its own sake such as claimed by artists in the Romantic era, and the arm’s length principle as the ‘constitution of cultural policies’ in the post WW2 Western world. Chapter 4 provides an overview of alternative voices which have challenged the dominant narrative. These include post colonial studies, cultural entrepreneurial studies and consumer behavior studies which in various ways propose alternative ways to lead and support the cultural sector. Chapter 5 links the discussions in chapter 3 and chapter 4 to leadership studies, notably to discussions of leader-centered orientations versus leading relationally orientations. The chapter concludes by suggesting a new sensibility towards understanding leadership and meditates on how this might be achieved, paying attentions to the possibilities of overcoming the putative crisis of legitimacy the inquiry is placed in. Chapter 6 relates a case-study of Malmoe City Library which endeavors into a difficult, yet very promising process of reformulating what a library may become in a contemporary context. This process challenges the dominant narrative and thus the current understanding of what a library should be, and this deviation from the dominant narrative challenges leadership. Chapter 7 assembles three different approaches to challenges the dominant narrative and to make new interpretive resources available to the understanding of leadership in the cultural sector. First, givrum.nu, a social movement working with arts, second, Mogens Holm, a leader in the cultural sector in a transition phase, and third, Copenhagen Phil, a classical symphony orchestra striving to avoid becoming a parallel society phenomenon. These case studies are conducted as written interviews with the cases, in an attempted un-edited form to also introduce relational processes informed by a power with relation to my own research project. Chapter 8 reflects on the case-studies in chapter 6 and chapter 7 in light of the two approaches to leadership discussed in chapter 5. It does so by linking my study to relational leadership theory in order to see how this theoretical field might inform my inquiry and how my inquiry might inform this field. It equally offers five possible reconstructions of the cases before concluding the research project by summing up contributions to the empirical field and the research fields, as well as by pointing to areas which could be further developed in future research. In line with the aspirations of the relational constructionist framework of the project, the inquiry does not offer a conclusion. Instead it encourages further reconstructions, thus submitting itself to the performative legitimization it argues in favor of