Engineering Quantum Defects in Silicon
Silicon, a mature platform for the semiconductor industry, has become a leading platform for future quantum technologies. As a high-purity material, it serves as a low-noise host for a variety of quantum defects. As a low-loss material, it is a
desirable substrate and material platform for next generation quantum devices. In this talk, I will discuss our efforts in tailoring the silicon host to facilitate new opportunities in quantum phononics and quantum photonics. First, atomic coherences of defects in silicon can be engineered to modify the macroscopic materials response. With strong coupling to electric field and crystal strain, the acceptor dopants can be deployed as atomic-scale piezoelectric transducers. I will describe our design and fabrication of the device platform for characterizing the piezoelectric response of a single acceptor in silicon. The ability to control the piezoelectric response of single dopants will pave the way towards large-scale piezoelectricity in silicon. Second, optically active defects are important building blocks for quantum networks. In this direction, we leverage the maturity of silicon photonics. We have realized waveguide-integrated single-photon emitters and observed two-photon interference from a single emitter in silicon. Realizing coherent emitters in silicon will be a significant step towards long-distance quantum networks.
Zihuai Zhang is a postdoctoral researcher in the group of Prof. Alp Sipahigil, working on solid-state quantum systems. He earned his Ph.D. in electrical and computer engineering in 2022 from Princeton University, where he worked on engineering coherent quantum defects in diamond in the group of Prof. Nathalie de Leon. He received his B.S. in physics in 2016 from the University of Science and Technology of China.