Ultrafast photocarrier dynamics in nanocrystalline ZnO sub(x)N sub(y) thin films

We examined the ultrafast dynamics of photocarriers in nanocrystalline ZnO sub(x)N sub(y) thin films as a function of compositional variation using femtosecond differential transmittance spectroscopy. The relaxation dynamics of photogenerated carriers and electronic structures are strongly dependent...

Full description

Saved in:
Bibliographic Details
Published in:Optics letters 2014-09, Vol.39 (17), p.5062-5065
Main Authors: Shin, Taeho, Lee, Eunha, Sul, Soohwan, Lee, Hyungik, Ko, Dong-Su, Benayad, Anass, Kim, Hyun-Suk, Park, Gyeong-Su
Format: Article
Language:English
Subjects:
Dynamics
Femtosecond
Nanocrystals
Phases
Thin films
Time
Transmittance
Zinc oxide
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We examined the ultrafast dynamics of photocarriers in nanocrystalline ZnO sub(x)N sub(y) thin films as a function of compositional variation using femtosecond differential transmittance spectroscopy. The relaxation dynamics of photogenerated carriers and electronic structures are strongly dependent on nitrogen concentration. Photocarriers of ZnO sub(x)N sub(y) films relax on two different time scales. Ultrafast relaxation over several picoseconds is observed for all chemical compositions. However, ZnO and oxygen-rich phases show slow relaxation (longer than several nanoseconds), whereas photocarriers of films with high nitrogen concentrations relax completely on subnanosecond time scales. These relaxation features may provide a persistent photocurrent-free and prompt photoresponsivity for ZnO sub(x) N sub(y) with high nitrogen concentrations, as opposed to ZnO for display applications.
ISSN:0146-9592
1539-4794
DOI:10.1364/OL.39.005062