Optical spectroscopy of colloidal CdSe semiconductor nanostructures

Doctoral Dissertation

Abstract

Using high-spatial-resolution time-resolved and temperature-dependent spectroscopy, this dissertation investigates emission properties of CdSe nanowires (NWs) synthesized using solid-liquid-solid (colloidal) growth. Temperature-dependent near- field scanning optical microscopy (NSOM) achieved spatial resolution of ~50 nm and imaged single NWs having wurtzite(WZ)-zincblende(ZB) polytype structure. Temperature-dependent NSOM and micro-photoluminescence (ÌåPL) spectra produce s- shape peak emission energy dependence on temperature, which reveal the formation of band-tail states in the NWs due to the variation of the polytype structure along the length of the NW. Time-resolved photoluminescence (TRPL) measures emission decay data that shows type-I band alignment between the WZ-ZB heterojunction due to the spectral dependence of the emission decay: the decay times decrease as the energy decreases. Finally, a robust rate equation model was completed for a single NW that produces theoretical calculations for the measurements.

Attributes

Attribute NameValues
URN
  • etd-06172011-075105

Author Joseph Bruce Herzog
Advisor Doug Hall
Contributor Greg Snider, Committee Member
Contributor Doug Hall, Committee Member
Contributor James L. Merz, Committee Co-Chair
Contributor Alexander Mintairov, Committee Co-Chair
Contributor Debdeep Jena, Committee Member
Degree Level Doctoral Dissertation
Degree Discipline Electrical Engineering
Degree Name Doctor of Philosophy
Defense Date
  • 2011-06-14

Submission Date 2011-06-17
Country
  • United States of America

Subject
  • micro photoluminescence

  • CdSe

  • Nanowires

  • NWs

  • spectroscopy

  • NSOM

  • TRPL

Publisher
  • University of Notre Dame

Language
  • English

Record Visibility and Access Public
Content License
  • All rights reserved

Departments and Units

Files

Please Note: You may encounter a delay before a download begins. Large or infrequently accessed files can take several minutes to retrieve from our archival storage system.