Quantum optics with color center in diamond

International Conference on Quantum Physics and Nuclear Engineering

March 14-16, 2016 London, UK

Alexander Kubanek

Ulm University, Germany

Scientific Tracks Abstracts: J Laser Opt Photonics

Abstract :

Implementing efficient, highly controllable light-matter interfaces is essential to realizing the goal of solid-state quantum networks. The nitrogen-vacancy (NV) center in diamond is a promising candidate for such interfaces due to favorable properties, such as long coherence times or single shot readout capabilities. Creating optical links between remote NV centers was an outstanding challenge until the recent demonstration of photon-mediated spin-spin entanglement between NV centers separated by three meters. I will present robust control of two remote NV centers demonstrating Hong-Ou-Mandel interference to verify the indistinguishability of photons produced by remote NV centers. The NV center�s application as quantum register depends on the ability to resonantly drive closed cycling transitions and closed lambda transitions with high fidelity. The fidelity can be degraded by phonon-induced mixing within the excited state manifold, which can provide unwanted non-radiative decay channels. I will present detailed investigation of phonon-induced mixing mechanism. Besides the importance to control phonon processes for applications of the NV center in Quantum Information, the NV center�s broad range of applications as sensors relies on the ability to initialize and readout the electronic state with off-resonant laser light. Both, initialization and read out rely on an inter-system crossing (ISC) process into a meta-stable state, a phonon-assisted shelving process that has not been fully explained. We have measured the ISC rate for different excited states and developed a model that unifies the phonon-induced mixing and ISC mechanisms. Finally, I will give an outlook into recent developments with other color centers in diamond.

Biography :

Alexander Kubanek has completed his PhD from Max-Planck Institute of Quantum Optics and Technical University Munich (Germany). He spent 4 years as Post-Doctoral Fellow/Research Associate at Physics Department of Harvard University. Since 2014, he is Carl-Zeiss Professor at Quantum Optics Institute of Ulm University. He was Fellow of Bavarian Network of Excellence and International PhD-Program Quantum Computing, Communication and Control and Feodor Lynen Fellow of Alexander von Humboldt Foundation. He has publication papers in Nature, Nature Physics and Physical Review Letters.

Email: alexander.kubanek@uni-ulm.de