Harada, N., Shoyama, H., Boonmong, N., Mizukami, K., Watanabe, Y., Zhao, P., Ehara, M., Sasaki, Y., Kimizuka, N. (2026). Sterically protected π-electron systems for efficient solid-state photon upconversion. Nature Communications. https://doi.org/10.1038/s41467-026-73898-0