Nuclear Science User Facilities 30 Yutai Katoh Materials scientist Yutai Katoh credits an elemen- tary school science experi- ment—the construction of a simple radio from a germanium diode and a crystal earphone—with sparking his love of science and engineering. His resume since then includes working with teams that developed plasma-facing materials for a fusion reactor at Japan’s National Institute for Fusion Science (NIFS), and a high-density silicon carbide matrix that led to accident tolerant fuels for conventional and advanced light water reactors. Now, in Katoh’s current job as a program manager for fusion mate- rials science and advanced nuclear materials at Oak Ridge National Labo- ratory, he hopes his contributions will continue to promote the safety and acceptance of nuclear power. Katoh grew up inTokyo, Japan, the son of a real estate developer and a pharmacist. In high school, his heroes included Soichiro Honda and Masaru Ibuka, the founders of Honda Motor Company and Sony, respectively. In college, he developed an interest in fusion and eventually began pursing a degree in materials science engineering. “I read introductory books and arti- cles about fusion energy and realized that superconducting materials are among the key technologies,” Katoh said. “This was the time when the high temperature superconductor boom was in its beginning.” During his junior year, a professor noticed Katoh’s ability to design and build electronic circuits and offered to become his graduate adviser. “The group was studying radiation effects in fusion materials, which resonated with my interest,” Katoh said. “The group was building a new ion irradiation facility, and my project had a side focus on building electronics for beam current profiling and electron beam heating.” Katoh stayed with the group as he earned his Ph.D. studying radiation effects in steels for nuclear applications. From there, Katoh went to the newly founded NIFS. His job was to assist with plasma-facing components (PFC) engineering in support of experiments using the Large Helical Device stellarator, a nuclear fusion research device that uses magnetic fields to control fusion plasma. “There was a huge gap between materials science and PFC engi- neering,” Katoh said. “I didn’t realize at that time that the gap would stay as a challenge for fusion energy devel- opment for decades to come.”