Single molecule quantum-confined Stark effect measurements of semiconductor nanoparticles at room temperature

Kyoungwon Park, Zvicka Deutsch, J. Jack Li, Dan Oron, Shimon Weiss

Research output: Contribution to journalArticle

65 Citations (Scopus)

Abstract

We measured the quantum-confined Stark effect (QCSE) of several types of fluorescent colloidal semiconductor quantum dots and nanorods at the single molecule level at room temperature. These measurements demonstrate the possible utility of these nanoparticles for local electric field (voltage) sensing on the nanoscale. Here we show that charge separation across one (or more) heterostructure interface(s) with type-II band alignment (and the associated induced dipole) is crucial for an enhanced QCSE. To further gain insight into the experimental results, we numerically solved the Schrödinger and Poisson equations under self-consistent field approximation, including dielectric inhomogeneities. Both calculations and experiments suggest that the degree of initial charge separation (and the associated exciton binding energy) determines the magnitude of the QCSE in these structures.

Original languageEnglish
Pages (from-to)10013-10023
Number of pages11
JournalACS nano
Volume6
Issue number11
DOIs
Publication statusPublished - Nov 27 2012

    Fingerprint

Keywords

  • nanorod
  • quantum dot
  • quantum-confined Stark effect
  • type-I band alignment
  • type-II band alignment
  • voltage sensing
  • wave function engineering

ASJC Scopus subject areas

  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

Cite this