清华大学材料科学与工程研究院《材料科学论坛》学术报告

报告时间：2025年11月12日下午15:00-17:00

报告人：Dr. Pham Nam Hai（东京科学大学）

报告地点：清华大学逸夫技术科学楼A205学术报告厅

邀请人：宋成老师

报告题目：Topological materials: from fundamental researches to industrial applications

报告简介：

Topological materials—including topological insulators and Dirac/Weyl semimetals—host surface states with Dirac dispersion and enable phenomena such as the quantum spin Hall effect, the quantum anomalous Hall effect, and the chiral anomaly. Yet their room-temperature device utility is often limited by epitaxial growth requirements and poor thermal robustness.

In this talk, I will summarize our studies of the room-temperature giant spin Hall effect in BiSb and YPtBi, positioning them as leading candidates for spintronic devices. Using industrial magnetron sputtering on Si/SiOx and achieving ≥400 °C thermal stability for CMOS compatibility, we demonstrate high-output spin Hall sensors for 4 Tbit/in² HDD technology and ultrafast (~1 ns), ultralow-power (requiring <10% of the power of conventional stacks) SOT-MRAM for AI applications. These proofs of concept and process-level advances have led to long-term collaborations with major semiconductor and storage companies, including TDK and Kioxia (Japan), Samsung (Korea), and Western Digital (US). By aligning materials discovery with industry requirements, we bridge fundamental topological physics and commercially relevant device applications.

报告人简介：

Pham Nam Hai is Professor and Vice-Head of Electrical and Electronic Engineering at the Institute of Science Tokyo (formerly Tokyo Institute of Technology), specializing in spintronics. His work spans ferromagnetic nanoclusters and semiconductors, ferromagnet/semiconductor hybrids, and topological insulators and semimetals, with applications to spintronics and AI. He serves as a representative member of the Japan Society of Applied Physics and has held editorial roles at the Magnetics Society of Japan (MSJ), including Editor-in-Chief (Spintronics). He has served on program committees for major meetings such as the Conference on Magnetism and Magnetic Materials (MMM). As a research director for Japan Science and Technology Agency projects, he has collaborated with R&D groups at Kioxia, TDK, Samsung, and Western Digital. Honors include the SSDM Young Researcher Award (2009), Ando Memorial Award (2014), Marubun Research Award (2017), German Innovation Award—Gottfried Wagener Prize (2019), Asian Scientist 100 (2020), and MSJ Outstanding Research Award (2020).