1. Department of Physics and Chemistry, DGIST, Daegu 42988, Republic of Korea
2. SK Hynix Inc., Icheon 17336, Republic of Korea
3. Department of Physics, University of Ulsan, Ulsan 44610, Republic of Korea
4. Convergence Research Institute, DGIST, Daegu 42988, Republic of Korea
5. Department of Materials Science and Engineering, Korea University, Seoul 02841, Republic of Korea