Abstract: Fault-tolerant quantum computation requires further advances in lowering physical qubit error rates in scalable architectures [1]. In this talk, I will present our work on superconducting quantum devices to reduce error rates and resource overheads in processors.  I will discuss how defects [2] and interfaces [3] in silicon limit superconducting qubit performance. I will present our discovery of interface piezoelectricity at a superconductor-silicon junction and the impact of this effect on superconducting qubits. I will discuss how phononic engineering might suppress these loss channels [4]. If time permits, I will also present progress on developing silicon photonic quantum repeater nodes based on recently discovered telecom-band color centers in silicon [5,6]. 

[1] Google Quantum AI, arXiv:2408.13687v1  (2024)

[2] Z Zhang*, K Godeneli*, et al., arXiv:2402.17155 (2024) 

[3] H. Zhou et al. , arXiv: 2409.10626 (2024)

[4] M Odeh et al., arXiv:2312.01031 (2023)

[5] Y. Xiong et al., Science Advances 9 (40), eadh8617 (2023) 

[6] L. Komza et al. Nature Communications 15, 6920 (2024) 

Bio:  Alp Sipahigil is the Ping & Amy Chao Family Assistant Professor of Electrical Engineering and Computer Sciences at the University of California, Berkeley. He has joint appointments as a Faculty Scientist at the Materials Sciences Division at Lawrence Berkeley National Laboratory and a supporting appointment at UC Berkeley Physics. He leads the Berkeley Quantum Devices Group which focuses on solid-state device research to advance quantum computation, communication and sensing. His group studies a wide range of physical systems including superconducting quantum circuits, color centers, integrated photonics and phononics. Prior to joining Berkeley in 2021, he was an Institute for Quantum Information and Matter postdoctoral scholar at Caltech. He received his Ph.D. in Physics from Harvard University in 2017 and his B.S. degrees in Physics and Electrical Engineering from Bogazici University in 2010.