Share Email Print
cover

Proceedings Paper

Ultrafast carrier dynamics and laser action in ZnO nanowires
Author(s): Marijn A. M. Versteegh; Ruben E. C. van der Wel; Benjamin J. M. Brenny; Bas Zegers; Wouter Ensing; Jaap I. Dijkhuis
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

We have examined ultrafast carrier dynamics and light amplification in ZnO nanowires following subpicosecond excitation at room temperature. We performed time- and wavelength-resolved pump-probe transmission and gain measurements on a 'forest' of 100- to 500-nm thick and 20-μm long nanowires, epitaxially grown on a sapphire wafer. Measurements were done using 267-nm pump pulses for direct, but inhomogeneous excitation, and 800-nm pulses to achieve homogeneous excitation via three-photon absorption. At the highest fluences, both for 267-nm and 800-nm pump pulses, a degenerate electron-hole plasma (EHP) is generated with carrier densities of 1025 m-3 or higher. We observed strong amplification of the probe, accompanied by a rapid decay (~ 1.5 ps) of the charge carriers. Below ~ 1025 m-3, the EHP becomes non-degenerate and the decay much slower. A dip in the pump-probe signal was observed, caused by ionization of probe exciton-polaritons by the pump. This effect allows for a measurement of the exciton-polariton dispersion relation and enhanced light-matter interaction in ZnO nanowires.

Paper Details

Date Published: 6 February 2009
PDF: 9 pages
Proc. SPIE 7214, Ultrafast Phenomena in Semiconductors and Nanostructure Materials XIII, 721413 (6 February 2009); doi: 10.1117/12.809250
Show Author Affiliations
Marijn A. M. Versteegh, Univ. Utrecht (Netherlands)
Ruben E. C. van der Wel, Univ. Utrecht (Netherlands)
Benjamin J. M. Brenny, Univ. Utrecht (Netherlands)
Bas Zegers, Univ. Utrecht (Netherlands)
Wouter Ensing, Univ. Utrecht (Netherlands)
Jaap I. Dijkhuis, Univ. Utrecht (Netherlands)


Published in SPIE Proceedings Vol. 7214:
Ultrafast Phenomena in Semiconductors and Nanostructure Materials XIII
Kong-Thon Tsen; Jin-Joo Song; Markus Betz; Abdulhakem Y. Elezzabi, Editor(s)

© SPIE. Terms of Use
Back to Top