Spectroscopic evidence for temperature-dependent convergence of light- and heavy-hole valence bands of PbQ (Q = Te, Se, S)J. Zhao, C. D. Malliakas, K. Wijayaratne, V. Karlapati, N. Appathurai, D. Y. Chung, S. Rosenkranz, M. G. Kanatzidis and U. ChatterjeeEPL, 117 2 (2017) 27006DOI: https://doi.org/10.1209/0295-5075/117/27006