“…Furthermore, to study the exciton–phonon coupling, Raman spectroscopy is conducted (Figure c) and records two modes: 123 cm –1 (∼15.3 meV) and 141 cm –1 (∼17.5 meV), corresponding to transverse-optical (TO, E TO ) and LO phonon energy ( E LO ), respectively. The value of E LO agrees reasonably with those reported for other inorganic semiconductors, 21 meV in CdTe, 35 meV in GaAs, 31 meV in ZnSe, and 38 meV in CdS, and is consistent with former reports in bulk HgTe, , confirming the weak size dependency of LO phonon energy. Therefore, the E LO value is expected as unchanged in our size-dependent experiment.…”