Formation and precise geometry control of SNAP microresonators by external electrostatic fields

In SNAP (Surface nanoscale axial photonics) resonators propagation of a slow whispering gallery mode along an optical fiber is controlled by nanoscale variation of the effective radius of the fiber [1]. Similar behavior can be realized in so - called nanobump microresonators in which the introduced variation of the effective radius is asymmetric, i.e. depends on the axial coordinate [2]. The possibilities of realization of such structures “on the fly” in an optical fiber by applying external electrostatic fields to it is discussed in this work. It is shown that local variations in effective radius of the fiber and in its refractive index caused by external electric fields can be large enough to observe SNAP structure - like behavior in an originally flat optical fiber. Theoretical estimations of the introduced refractive index and effective radius changes and results of finite element calculations are presented. Various effects are taken into account: electromechanical (piezoelectricity and electrostriction), electro-optical (Pockels and Kerr effects) and elasto-optical effect. Different initial fibre cross-sections are studied. The aspects of use of linear isotropic (such as silica) and non-linear anisotropic (such as lithium niobate) materials of the fiber are discussed. REFERENCES [1] M. Sumetsky, J. M. Fini, Opt. Exp. 19, 26470 (2011). [2] L. A. Kochkurov, M. Sumetsky, Opt. Lett. 40, 1430 (2015).

Care-less spaces and identity construction:transition to secondary school for disabled children

There is a growing body of literature which marks out a feminist ethics of care and it is within this framework we understand transitions from primary to secondary school education can be challenging and care-less, especially for disabled children. By exploring the narratives of parents and professionals, we investigate transitions and self-identity, as a meaningful transition depends on the care-full spaces pupils inhabit. These education narratives are all in the context of privileging academic attainment and a culture of testing and examinations. Parents and professionals, as well as children are also surveyed. Until there are care-full education processes, marginalisation will remain, impacting on disabled children’s transition to secondary school and healthy identity construction. Moreover, if educational challenges are not addressed, their life chances are increasingly limited. Interdependent caring work enables engagement in a meaningful education and positive identity formation. In school and at home, care-full spaces are key in this process.