Unusual terahertz-wave absorptions in $\delta/\alpha$-mixed-phase FAPbI$_3$ single crystals: interfacial phonon vibration modes
Inhee Maeng, Seungjun Lee, E.Q. Han, Yurou Zhang, Seung Jae Oh, Masakazu Nakamura, Jung-Ho Yun, Lianzhou Wang, Young-Kyun Kwon, and Min-Cherl Jung, NPG Asia Mater. 13, 75 (2021).
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