Fluorescence modulation in single CdSe quantum dots by moderate applied electric fields

Journal Article · Tue Jan 21 00:00:00 EST 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4856315· OSTI ID:22275706

LeBlanc, Sharonda J. ^[1]; McClanahan, Mason R.; Moyer, Tully; Moyer, Patrick J. ^[1]; Jones, Marcus ^[2]

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1. Department of Physics and Optical Science, University of North Carolina at Charlotte, 9201 University City Boulevard, Charlotte, North Carolina 28223 (United States)
2. Department of Chemistry, University of North Carolina at Charlotte, 9201 University City Boulevard, Charlotte, North Carolina 28223 (United States)

Single molecule time-resolved fluorescence spectroscopy of CdSe/ZnS core-shell quantum dots (QDs) under the influence of moderate applied electric fields reveals distributed emission from states which are neither fully on nor off and pronounced changes in the excited state decay. The data suggest that a 54 kV/cm applied electric field causes small perturbations to the QD surface charge distribution, effectively increasing the surface trapping probability and resulting in the appearance of gray states. We present simultaneous blinking and fluorescence decay results for two sets of QDs, with and without an applied electric field. Further kinetic modeling analysis suggests that a single trapped charged cannot be responsible for a blinking off event.

• OSTI ID: 22275706
• Journal Information: Journal of Applied Physics, Vol. 115, Issue 3; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
77 NANOSCIENCE AND NANOTECHNOLOGY
CADMIUM SELENIDES
CHARGE DISTRIBUTION
ELECTRIC FIELDS
EXCITED STATES
FLUORESCENCE
FLUORESCENCE SPECTROSCOPY
HETEROJUNCTIONS
INTERFACES
MODULATION
MOLECULES
QUANTUM DOTS
SURFACES
TIME RESOLUTION
TRAPPING
ZINC SULFIDES