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.

“With the NSF’s generous support, which will combine with resources that MIT will devote as well as participation from a broad consortium of government and industry partners, we are going to tackle the educational and learning challenges in quantum information science with an innovative, interdisciplinary approach to training the new generation of QIS scientists and engineers.”

—Isaac Chuang, Director, iQuISE, and Associate Professor of Electrical Engineering and Associate Professor of Physics