Towards interfacing single photons emitted from Dibenzoterrylene with rubidium ensemble quantum memories

Abstract

Photonic quantum information processing is a pivotal aspect of the emerging quantum tech- nology landscape, with a wide range of applications in quantum computing, communication, simulation and sensing. The use of single photons for these applications is of immense interest, but requires both the generation of single photons and the ability to interact them separately, often relying on probabilistic processes. The first part of this thesis showcases work on the generation of single photons, utilizing an organic molecule, Dibenzoterrylene (DBT), doped into an anthracene (Ac) crystal. We will in- troduce a comprehensive theoretical framework for characterizing these molecules, and present experimental results where the wavlength of emission from DBT is tuned through three dif- ferent tuning mechanisms. Additionally, we will explore techniques for enhancing the emission properties of DBT, before finally demonstrating single photon emission from DBT in a novel host matrix: para-Terphenyl. In the second part of this thesis, we shift our focus to quantum memories - critical devices capable of storing and on-demand recall of quantum states of light, required to overcome the limitations of probabilistic photon-photon interactions. We will derive equations of motion governing the memory interaction with single photons and an ensemble of atoms. Next, we will explore methods for optimizing the memory interaction, while increasing the complexity of our model to more accurately resemble an interface between photons emitted from DBT/Ac and a rubidium (Rb) vapour, near resonant with the DBT/Ac. Finally, we will present the major challenges facing these systems and potential avenues for overcoming them. The results presented in this thesis pave the way for interfacing photons emitted from DBT with quantum memories based on a Rb ensemble.