Highly efficient, deep-ultraviolet luminescence in hBN moiré quantum wells. - Hong, Chengyun; Zhao, Fangzhou; Song, Su-Beom; Yoon, Sangho; Jeon, Seong-Joon; Khan, M. Ajmal; Tao, Ye; Yang, Dong-Hwan; Lee, Wanhee; Kim, Junho; Yang, Sera; Cho, Hyungseob; et al. (Science, 2026)