EE Student Information

Q-FARM presents "Spin qubits in silicon carbide for quantum technologies"

Spin qubits in silicon carbide for quantum technologies
Thursday, April 29, 2021 - 12:30pm
r: Chris Anderson (Univ of Chicago)
Abstract / Description: 

Defect spin qubits in silicon carbide (SiC) with associated nuclear spin quantum memories can leverage near-telecom emission and wafer-scale semiconductor device engineering for creating quantum technologies. Here, I highlight recent advances with the neutral divacancy defect (VV0) in SiC within the context of long-distance quantum communication and repeater schemes. Broadly, I will illustrate how quantum states can be controlled, tuned, and enhanced through their integration into SiC mechanical, photonic, and electrical devices. I will first describe the isolation of single VV0 defects in functional SiC optoelectronic devices, which allows for deterministic charge state control and terahertz tuning, but also surprisingly eliminates spectral diffusion in the optical structure of these defects. I will then discuss the entanglement and control of nuclear spin registers, and show how isotopic engineering can enhance both nuclear quantum memories and electron spin coherence times, while also demonstrating high fidelity control (99.98%), initialization, and readout. Briefly, I will further highlight recent results that universally protect spin coherence from electrical, magnetic, and thermal noise, resulting in T2*>20 ms in a naturally abundant crystal. This suite of results establishes SiC as a promising platform for scalable quantum science with optically-active spins.

Bio: Chris is currently a postdoctoral scholar in the research group of David Awschalom at the University of Chicago in the Pritzker School of Molecular Engineering. Recently, he completed his PhD in Physics in the same group. Generally, Chris works on developing the physics and devices that enable the next generation of quantum technologies using spins in semiconductors. He was awarded a NDSEG fellowship for his graduate work. Chris was a researcher in spintronics in Vanessa Sih's group, and worked on ultrafast chemical physics in Roseanne Sension's group at the University of Michigan, where he received a B.S in Chemistry and Physics. Chris has also worked on attosecond laser systems at the Max-Planck Institute for Nuclear Physics, and spent his early years as a molecular biology and genomics researcher.