講演情報
[22p-21C-3]Integrated analysis of the A1(LO) and E2(high) modes in GaInN/GaN heterostructures by Raman spectroscopy
〇(DC)KhaingShwe TheeEi1, Tatsuya Asaji1, Bei Ma1, Daisuke Iida2, Mohammed A. Najmi2, Kazuhiro Ohkawa2, Yoshihiro Ishitani1 (1.Chiba Univ., 2.KAUST)
キーワード：
Microscopic Raman Spectroscopy、InGaN、LO phonon dynamics
Longitudinal optical phonon has a high probability of interaction with the electron system. GaInN crystals have significant spatial nonuniformity in alloy composition. This article mainly focuses on the LO phonon dynamics in a nonuniformity crystal system. The investigation of mode-energy variation when heating between E2(high) and A1(LO) modes in In0.05Ga0.95N/GaN heterostructures by using 325-nm laser with microscopic Raman spectroscopy. The peak energies of these modes shift to the lower energy sides by increasing the excitation power. The decrement for the E2(high) mode energy shows significant nonuniformity in temperature. In the mapping images of decrements in these energy modes, the decrement of the A1(LO) mode energy is lower than the surrounding region in the region of high decrement in the E2(high) mode energy. This result reveals that the local increase in the crystal temperature and the local increase in electron density can be simultaneously exhibited and investigated.