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Photonic Crystal Coupled to N-V Center in Diamond
Luca Marseglia
Abstract
In this work we aim to exploit one of the most studied defect color centers in diamond , the negatively charged nitrogen vacancy (NV -) color center, a three level system which emits a single photon at a wavelength of 637nm providing a possible deterministic single photon emitter very useful for quantum computing applications.Moreover the possibility of placing aNV -in a photonic crystal cavity will enhance the coupling between photons and NV -center.This could also allow us to address the ground state of the NV -center, whose spin, could be used as qubit.It is also remarkable to notice that for quantum computing purposes it is very useful to increase the light collection from the NV -centers, and in order to do that we performed a study of another structure, the solid immersion lens, which consists of an hemisphere whose center is at the position of an emitter, in this case the NV -center, increasing the collection of the light from it.In order to create these structures we used a method called focused ion beam which allowed us to etch directly into the diamond many different kinds of structures.In order to allow an interaction between these structures and the NV -centers we need to have a method to locate the NV -center precisely under the etched structures.We developed a new technique (Marseglia et al. (2011)) where we show how to mark a single NV -center and how to etch a desired structure over it on demand.This technique gave very good results allowing us to etch a solid immersion lens onto a NV -previously located and characterized, increasing the light collection from the NV -of a factor of 8×.