Nanoscale heat transport from Ge hut, dome, and relaxed clusters on Si(001) measured by ultrafast electron diffraction

Autor:	V Tinnemann, M. Horn-von Hoegen, T. Frigge, B. Hafke, B. Krenzer
Rok vydání:	2015
Předmět:	Diffraction Materials science Physics and Astronomy (miscellaneous) Silicon Ultrafast electron diffraction Time constant chemistry.chemical_element Physik (inkl. Astronomie) Epitaxy Molecular physics Crystallography chemistry Electron diffraction Heat transfer Cluster (physics)
Zdroj:	Applied Physics Letters. 106:053108
ISSN:	1077-3118 0003-6951
Popis:	The thermal transport properties of crystalline nanostructures on Si were studied by ultra-fast surface sensitive time-resolved electron diffraction. Self-organized growth of epitaxial Ge hut, dome, and relaxed clusters was achieved by in-situ deposition of 8 monolayers of Ge on Si(001) at 550 °C under UHV conditions. The thermal response of the three different cluster types subsequent to impulsive heating by fs laser pulses was determined through the Debye-Waller effect. Time resolved spot profile analysis and life-time mapping was employed to distinguish between the thermal response of the different cluster types. While dome clusters are cooling with a time constant of τ = 150 ps, which agrees well with numerical simulations, the smaller hut clusters with a height of 2.3 nm exhibit a cooling time constant of τ = 50 ps, which is a factor of 1.4 slower than expected.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b835c3edf556686a97f9414fdf2450e5 https://doi.org/10.1063/1.4907636 Zobrazit plný text záznamu