solid-state quantum memories
The coherent mapping of quantum information between light and matter is a crucial requirement in quantum information science. Here, we study the interaction between single photons and cryogenically cooled crystals doped with praseodymium rare-earth ions. Our objective is to store quantum states of light in long lived collective spin excitations and use it in the implementation of quantum repeater links.
Cold atomic ensembles
Cold atomic ensembles are currently one of the most advanced systems for the quantum control of light matter interaction at the single excitation level. Single collective spin excitations (so called super atoms) can be created in a heralded fashion and efficiently transferred into a single photon field, thanks to a collective interference between all the emitters. We are investigating various protocols to create, manipulate and transfer to light single collective spin excitations.
single ions in nanocrystals
In this project, we gain efficient access to individual ions and small ensembles by coupling solid-state nano-structures to a high finesse optical fibre micro-cavity. Purcell enhancement can enhance the emission rate by several orders of magnitude, thereby making the weak transitions bright. As this emission is in the mode of the cavity, it also allows for a very efficient interaction.
