Dec. 3: Professor Christoph Becher (Saarbrucken University) on “Prospects of SiV centers in diamond for quantum information”

Title: Prospects of SiV centers in diamond for quantum information

Location: 26-214, Thursday Dec 3, Noon-1pm. Pizza at 11:45!
(Feel free to bring your own cup and plate)

Abstract: Spin impurities in diamond are versatile tools for a wide range of solid-state-based quantum technologies. The most prominent example is the nitrogen vacancy (NV) center providing very long spin coherence times. On the other hand, its optical properties are limited by a dominant emission into a very broad phonon sideband hindering efficient optical spin access. Thus, identifying a spin impurity which offers sufficient quality in both photonic and spin properties remains a challenge. Silicon vacancy (SiV) centers have attracted large interest due to their spin-accessible optical transitions [1,2] and the quality of their optical spectrum, i.e. narrow zero phonon lines and weak phonon sidebands [3]. What remains largely unexplored so far is the spin coherence time being essential for applying SiV centers as spin-photon quantum interface. I report on the nature of the SiV electronic structure, selection rules giving rise to spin-selective fluorescence, and all-optical access to spin coherence in the ground state using coherent population trapping [4]. We further investigate the role of phonon-assisted coupling between orbital states as a source of irreversible spin decoherence. Our results indicate that all-optical coherent control of silicon-vacancy spins is feasible.

“The students in MIT’s new NSF training program will be encouraged to cross disciplines, and develop a common fellowship with their peers. We will also address training for post-academic jobs directly by connecting students to government and industrial members of the iQuISE Consortium.”

—Seth Lloyd, Co-Director, iQuISE, and Professor of Mechanical Engineering and Professor of Engineering Systems