Quantum control of spin centers in silicon carbide with microcavities

• Applicant: Privatdozent Dr. Georgy Astakhov
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2016 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 323228505

Microcavities are ideal interfaces between photons as flying qubits and electron spins as stationary qubits, as they strongly enhance the interaction between light and matter. They are therefore among the foremost tools in the study and manipulation of the quantum mechanical nature of light, matter and their interactions. Silicon carbide (SiC) is a very promising material platform for wafer-scale spintronics and quantum information processing. First, this is because SiC is a material compatible with CMOS (complementary metal-oxide-semiconductor) technology, allowing construction of integrated circuits on a SiC wafer, just as silicon. Second and most importantly, spin centers in this material, particularly silicon vacancies, demonstrate an exceptionally long spin coherence time already in commercial wafers and they can be optically controlled even at the single-spin level. However, the main obstacles against applications of these centers are a low count rate from single centers and a low spin readout contrast.In this project, we will couple a single spin color center to a high quality resonator formed by a SiC chip and a silicon micromirror. This type of micromirror offers excellent surface quality, small radii of curvature and a direct path to scalability. Using resonant excitation and detection schemes, we plan to increase the spin readout contrast to above 50%. Finally, we plan to demonstrate spin-photon entanglement with a silicon vacancy in SiC, which is an important step towards implementation of quantum repeaters and networks.

• DFG Programme: Research Grants
• International Connection: Austria
• Partner Organisation: Fonds zur Förderung der wissenschaftlichen Forschung (FWF)
• Co-Investigator: Michael Trupke, Ph.D.