Hot-electron energy relaxation time in Ga-doped ZnO films.

Autor: Šermukšnis, E., Liberis, J., Ramonas, M., Matulionis, A., Toporkov, M., Liu, H. Y., Avrutin, V., Özgür, Ü., Morkoç, H.
Předmět:
Zdroj: Journal of Applied Physics; 2015, Vol. 117 Issue 6, p065704-1-065704-8, 8p, 1 Diagram, 2 Charts, 5 Graphs
Abstrakt: Hot-electron energy relaxation time is deduced for Ga-doped ZnO epitaxial layers from pulsed hotelectron noise measurements at room temperature. The relaxation time increases from ~0.17 ps to ~1.8 ps when the electron density increases from 1.4×1017 cm-3 to 1.3×1020 cm-3. A local minimum is resolved near an electron density of 1.4×1019cm-3. The longest energy relaxation time (1.8 ps), observed at the highest electron density, is in good agreement with the published values obtained by optical time-resolved luminescence and absorption experiments. Monte Carlo simulations provide a qualitative interpretation of our observations if hot-phonon accumulation is taken into account. The local minimum of the electron energy relaxation time is explained by the ultrafast plasmon-assisted decay of hot phonons in the vicinity of the plasmon-LO-phonon resonance. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index