Publication
Title
Coherent level mixing in dot energy spectra measured by magnetoresonant tunneling spectroscopy of vertical quantum dot molecules
Author
Abstract
We study by magnetoresonant tunneling spectroscopy single-particle energy spectra of the constituent weakly coupled dots in vertical quantum dot molecules over a wide energy window. The measured energy spectra are well modeled by calculated spectra for dots with in-plane confinement potentials that are elliptical and parabolic in form. However, in the regions where two, three, or four single-particle energy levels are naively expected to cross, we observe pronounced level anticrossing behavior and strong variations in the resonant currents as a consequence of coherent mixing induced by small deviations in the nearly ideal dot confinement potentials. We present detailed analysis of the energy spectra, and focus on two examples of three-level crossings whereby the coherent mixing leads to concurrent suppression and enhancement of the resonant currents when the anticrossing levels are minimally separated. The suppression of resonant current is of particular interest since it is a signature of dark state formation due to destructive interference. We also describe in detail and compare two measurement strategies to reliably extract the resonant currents required to characterize the level mixing.
Language
English
Source (journal)
Physical review : B : condensed matter and materials physics. - Lancaster, Pa, 1998 - 2015
Publication
Lancaster, Pa : 2010
ISSN
1098-0121 [print]
1550-235X [online]
Volume/pages
81:24(2010), p. 245310,1-245310,15
ISI
000278606100003
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identification
Creation 08.07.2010
Last edited 03.11.2017
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