The embedding of the nitrogen-vacancy (NV) center in the diamond crystal lattice structure naturally involves the coupling to global vibrational (phonon) modes. However the coupling strength to these modes depends crucially on the dimensions of the diamond crystal. I will show that for crystals in the nanometer range, a well-separated acoustical mode spectrum paired with a significant and selective electron-phonon coupling can lead to discrete vibrational sidebands. Concepts are provided, that allow for harnessing the associated energy shift on the ground-excited state NV transition for coherent interactions within the ground state manifold. That way, conditional quantum gates can be constructed and further optimized by relying on a dispersive regime and by the combination with decoupling sequences.

In addition, a bottom-up approach for the creation of symmetric arrangements of NV centers will be presented. This is based on attaching nanodiamonds to a self-assembled scaffold of proteins (SP1). Besides first experimental results, concepts for the practical implementation of quantum operations in such systems are addressed. In particular, the creation of dynamically decoupled gate operations, the achievement of a uniform coupling and the ability for individual addressing.


Seminar, January 19, 2015, 12:00. Seminar Room

Hosted by Prof. Darrick Chang