Topic: Cuprate Superconducting Devices Enabled by Focused Helium Ion Beam Direct-writing
Speaker: Dr. LI Hao, Shanghai Institute of Microsystem and Information Technology (SIMIT)
Date and time: 14:00–15:30, February 28
Venue: Room 105, #5 Building of SPST
Host: ZHAI Xiaofang
Abstract:
The superior properties of superconducting devices in switching speed, power disspation, and detection sensitivity, provide them dominating advantages over counterparts in applications, such as quantum information science, advanced computing, biomagnetism and earth physics, on which homeland security, human health and natural resouces seriously rely. The discovery of cuprate superconductors in 1980s, especially Y-Ba-Cu-O with superconducting transition temperature above liquid nitrogen (77 K), ignited the scientific community and electronic industry on the illusion of an upcoming era of superconducting electronics. Unfortunately, the remaining mystery of microscopic mechanism of the cuprate superconductor and the nano-fabrication challenges posed beyond that times hindered the development of superconducting devices working at liquid nitrogen, which is inexhaustible and ~100 times cheaper than liquid helium. Here, Dr. LI would introduce focused helium ion beam (He-FIB) technique with ion energy ~30 keV and beam size ~0.5 nm and its application on cuprate superconducting devices, a new method proposed by his previous group, addressing the nano-fabrication problem well. Dr. LI will also discuss the challenging caused by materials on the uniformity of superconducting devices and urgent needs for high-quality cuprate films.
Biography:
Dr. LI Hao received his bachelor's degree at Jilin University in 2010, majoring in microelectronics. He received PhD degree in electronic science and technology at Tsinghua University in 2017. From 2017 to 2020, he worked as a postdoctoral researcher at University of California, Riverside. After which, he joined Kansas Unviersity and served as assistant professor until 2021. His research interests lie on superconducting electronics, nano-fabrication and nanoscale electronics. He is pioneering on cuprate superconducting devices based on focused helium ion beam nano-fabrication. In 2021, he joined Shanghai Institute of Microsystem and Information Technology as principal investigator and young researher. Dr. LI has published 23 peer-reviewed journal articles, including Applied Physics Letters, IEEE Transactions on Applied Superconductivity, and Supercondutor Science and Technology.