Published October 2012 | Version v1
Journal article Metadata-only

Investigation of ultrafast dynamics of CdTe quantum dots by femtosecond fluorescence up-conversion spectroscopy

Creators

  • 1. Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031 (China)
  • 2. Institute of Atomic and Molecular Physics, Anhui Normal University, Wuhu 241000 (China)
  • 3. College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000 (China)
  • 4. Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1090 GD Amsterdam (Netherlands)

Description

The ultrafast carrier relaxation processes in CdTe quantum dots are investigated by femtosecond fluorescence up-conversion spectroscopy. Photo-excited hole relaxing to the edge of the forbidden gap takes a maximal time of ∼ 1.6 ps with exciting at 400 nm, depending on the state of the photo-excited hole. The shallow trapped states and deep trap states in the forbidden gap are confirmed for CdTe quantum dots. In addition, Auger relaxation of trapped carriers is observed to occur with a time constant of ∼ 5 ps. A schematic model of photodynamics is established based on the results of the spectroscopy studies. Our work demonstrates that femtosecond fluorescence up-conversion spectroscopy is a suitable and effective tool in studying the transportation and conversion dynamics of photon energy in a nanosystem

Availability note (English)

Available from http://dx.doi.org/10.1088/1674-1056/21/10/107801

Additional details

Identifiers

DOI
10.1088/1674-1056/21/10/107801;

Publishing Information

Journal Title
Chinese Physics. B
Journal Volume
21
Journal Issue
10
Journal Page Range
[6 p.]
ISSN
1674-1056

INIS

Country of Publication
China
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
45015084
Subject category
S77: NANOSCIENCE AND NANOTECHNOLOGY;
Descriptors DEI
CADMIUM TELLURIDES; CHARGE CARRIERS; CONVERSION; ELECTRONIC STRUCTURE; FLUORESCENCE; FLUORESCENCE SPECTROSCOPY; HOLES; PHOTONS; QUANTUM DOTS; RELAXATION; TRAPPING; TRAPS
Descriptors DEC
BOSONS; CADMIUM COMPOUNDS; CHALCOGENIDES; ELEMENTARY PARTICLES; EMISSION; EMISSION SPECTROSCOPY; LUMINESCENCE; MASSLESS PARTICLES; NANOSTRUCTURES; PHOTON EMISSION; SPECTROSCOPY; TELLURIDES; TELLURIUM COMPOUNDS