High Quality Factor Confinement Of Bloch Surface Waves At Visible Wavelengths

We report the first experimental demonstration of high quality factor confinement of Bloch surface waves at visible wavelengths. The cavities consist of planar Fabry-Perot resonators that are fabricated on top of a Bloch surface supporting substrate. This work presents the design and fabrication methods used for the setting up of the experiment. Quality factors of the order of 2000 are measured. This work demonstrates that optical surface waves can be efficiently confined, and thus constitute a viable alternative to guided waves for on chip optical components and operations

High-Q side-coupled semi-2D-photonic crystal cavity

High-Q semi-2D-photonic crystal cavities with a tapered edge and side-coupled bus waveguide are demonstrated. With a quadratic design, the unloaded cavity presents a theoretical ultrahigh quality factor up to 6.7 × 10(7) for the condition that there are mere 34 holes in the propagated direction, which is pretty close to the 2D and 1D counterpart. Combined with a side-coupled bus waveguide, an all-pass-type cavity with a loaded quality factor (Q) of over 2.4 × 10(4) and an extinction ratio over 10 dB are experimentally demonstrated. An experimental loaded Q up to 1.1 × 10(5) are also achieved by tuning the coupling between the cavity and the bus waveguide, which is much larger than any reported surface-mode cavity. This cavity is quite suitable for sensors, filters and especially optomechanical devices thanks to the mechanical stability of the cavity and flexibility of the bus waveguide

Recent Experiments at Big Karl

Friendship is sometimes assumed to denote a very separate set of concerns to those which have traditionally been thought central to International Relations: sovereignty, states, and nations. Brought into relation to these themes the concern of friendship might appear at best novel or marginal – if it is to be considered pertinent at all. Yet there might be pause to reconsider this conclusion. In recent decades a body of literature has emerged which challenges this view (King and Smith (2007), Devere and Smith (2010), Oelsner and Vion (2011)). Could it be that this literature indicates something about the structure and implications of International Relations which might otherwise be overlooked? Moreover, does ‘friendship’ encourage a re-engagement and restructuring within the ontology of International Relations itself (cf. Berenskoetter 2007)? To pose this question is to consider the ways that friendship offers a challenge and alternative to both how International Relations is understood (its conceptualisation), and the kinds of things that it takes as its basic objects of study and concern (its ontology). This essay suggests that friendship does in fact offer such a challenge. Friendship is not so much an object or identifiable state, but a way of conceptualising relations. Friendship suggests that the focus for understanding both the state and the nation should be to see them as specialised friendship groups. Such a framework also alerts us to the numerous bonds of friendship which are left in more nebulous and fluid states. This remainder makes a reformation of the political possible, and forms one of the bases of change in the international order. This essay is analytical in character. It intends to provide an outline of the role of friendship in International Relations, and to illustrate this with reference to the state and nation. In the first part the conceptualisation of friendship will be explored (which also leads to comment on the more generic problem of conceptualisation itself). Here it is argued that rather than being understood to denote a specific and restricted relationship between discrete entities, friendship is a concept which helps to identify and understand a wider problematic. This problematic is the nature of the bonds between person and person, group and group, and the substantial affects and phenomena that these produce. As such friendship should not be thought to indicate an ‘ideal type’ against which the success of a ‘search’ for friendship in International Relations can be measured. Instead friendship can be thought of as indicating a set of concerns which are focused on identification and reciprocation within a framework of shared values. The concern here is not so much to define friendship, but to identify and analyse its dynamics and consequences. In this sense, friendship is not something ‘possessed’ but something that ‘is happening’. It is not something that can be detailed, but something that helps to structure and explain. The second part the essay proceeds to bring this conceptual framework to bear on two important concepts in International Relations; the state and the nation. By extending the analysis of friendship offered in the first part, here it is argued that both the state and the nation should not be taken to indicate defined (let alone discrete) entities, but are better understood to indicate a complex of concerns centred around the possibilities and affects of bonding. In short, both state and nation are specialised and highly effective instances of friendship. As such, both take pre-existing bonds of friendship and transform them into something new. The state and the nation are therefore significant crystallisations of friendship which emerge from, and transform, existing bonds. Importantly, in so doing they leave a remainder, and it is this underdeveloped friendship which provides the material for future change. The essay concludes that far from being irrelevant to an understanding of International Relations, friendship is central to it. Without an understanding and theorisation of the possibility of relations, both within and between states and nations, there can be no ‘international’. Indeed, it might not only offer a complement to existing approaches, but perhaps ultimately to dislodge the traditional lens shaped by the foci of sovereignty and power, replacing them instead with a focus on a more complex order of identifications, reciprocations, and shared values