Takeshi Ohshima is currently the director of Quantum Materials and Application Research Centers (QUARC), Takasaki Advanced Radiation Research Institute, National Institutes for Quantum Science and Technology (QST). He received his Ph.D. in Materials Science from the University of Tsukuba in 1994. After his Ph.D, he joined the Japan Atomic Energy Research Institute (now QST), Japan in 1994. Since 2020 he has been a department director of QST. He also holds a position as a Guest Professor at Faculty of Pure and Applied Science, University of Tsukuba, Japan. His research interests are radiation effects on semiconductor materials and devices/solar cells for space and nuclear applications. He also studies defect engineering (creation of color centers and spin defects) for quantum technologies.