1. Graduate School of Engineering Nagoya University Furo‐cho Chikusa‐ku Nagoya 464‐8603 Japan
2. Institute of Materials and Systems for Sustainability (IMaSS) Nagoya University Furo‐cho Chikusa‐ku Nagoya 464‐8603 Japan
3. Center for Advanced Intelligence Project RIKEN Nihonbashi Chuo‐ku Tokyo 103‐0027 Japan
4. GaN Advanced Device Open Innovation Laboratory (GaN‐OIL) National Institute of Advanced Industrial Science and Technology (AIST) Nagoya University Furo‐cho Chikusa‐ku Nagoya 464‐8601 Japan