1. Organic Optoelectronic Device Lab. (OODL) Department of Information Display Kyung Hee University 26, Kyungheedae‐ro, Dongdaemun‐gu Seoul 02447 Republic of Korea
2. LG Display R & D center LG Science park, 30, Magokjungang 10‐ro, Gangseo‐gu Seoul 07796 Republic of Korea