Blue emission at atomically sharp 1D heterojunctions between graphene and h-BN oleh Gwangwoo Kim, Kyung Yeol Ma, Minsu Park, Minsu Kim, Jonghyuk Jeon, Jinouk Song, José Eduardo Barrios-Vargas, Yuta Sato, Yung-Chang Lin, Kazu Suenaga, Stephan Roche, Seunghyup Yoo, Byeong-Hyeok Sohn, Seokwoo Jeon, Hyeon Suk Shin