Interface inter-atomic electron-transition induced photon emission in contact-electrification Li, Ding ; Xu, Cheng ; Liao, Yanjun ; Cai, Wenzhe ; Zhu, Yongqiao ; Wang, Zhong Lin Abstract Publication: Science Advances Pub Date: September 2021 DOI: 10.1126/sciadv.abj0349 Bibcode: 2021SciA....7..349L