Relaxation of Second-Harmonic Generation in Guest/Host Polymers Poled by Indium-Tin Oxide Sandwich Electrodes

Stephan Schüssler, Ranko Richert, Heinz Bässler

Research output: Contribution to journalArticle

31 Scopus citations

Abstract

Second-harmonic generation (SHG) is used to monitor reorientation dynamics of 4-(dimethylamino)- 4′-nitrostilbene doped at 1 wt % in poly(ethyl methacrylate) within a temperature range of TG ± 30 K. Special emphasis is put on a systematic analysis of experimental conditions and their severe impact on SHG data for samples which are poled in an indium-tin oxide (ITO)-sandwich-electrode configuration. These effects include thermal history, local heating effects due to laser focus, importance of dopant concentration, physical aging, details of the poling procedure, and charge-injection effects. The fast initial response of the SHG signal upon field switching is attributed to space charge effects. We show how the problem of SHG reproducibility can be overcome with appropriate experimental conditions. Analysis of the reliable data is based on a Gaussian distribution of energy barriers for the dopant relaxation which yields superior fits compared to a stretched exponential function. The Arrhenius-like behavior of the mean SHG decay rate points toward a decoupling of the dopant motion from the bulk α-process of the polymer host. Additionally, a novel repoling technique and its implications are discussed.

Original languageEnglish (US)
Pages (from-to)4318-4326
Number of pages9
JournalMacromolecules
Volume27
Issue number15
DOIs
StatePublished - Jul 1 1994
Externally publishedYes

ASJC Scopus subject areas

  • Organic Chemistry
  • Polymers and Plastics
  • Inorganic Chemistry
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Relaxation of Second-Harmonic Generation in Guest/Host Polymers Poled by Indium-Tin Oxide Sandwich Electrodes'. Together they form a unique fingerprint.

  • Cite this