TY  - JOUR
A1  - Rudno-Rudziński, W.
A1  - Syperek, M.
A1  - Andrezejewski, J.
A1  - Maryński, A.
A1  - Misiewicz, J.
A1  - Somers, A.
A1  - Höfling, S.
A1  - Reithmaier, J. P.
A1  - Sęk, G.
T1  - Carrier delocalization in InAs/InGaAlAs/InP quantum-dash-based tunnel injection system for 1.55 μm emission
JF  - AIP Advances
N2  - We have investigated optical properties of hybrid two-dimensional-zero-dimensional (2D-0D) tunnel structures containing strongly elongated InAs/InP(001) quantum dots (called quantum dashes), emitting at 1.55 μm. These quantum dashes (QDashes) are separated by a 2.3 nm-width barrier from an InGaAs quantum well (QW), lattice matched to InP. We have tailored quantum-mechanical coupling between the states confined in QDashes and a QW by changing the QW thickness. By combining modulation spectroscopy and photoluminescence excitation, we have determined the energies of all relevant optical transitions in the system and proven the carrier transfer from the QW to the QDashes, which is the fundamental requirement for the tunnel injection scheme. A transformation between 0D and mixed-type 2D-0D character of an electron and a hole confinement in the ground state of the hybrid system have been probed by time-resolved photoluminescence that revealed considerable changes in PL decay time with the QW width changes. The experimental discoveries have been explained by band structure calculations in the framework of the eight-band k·p model showing that they are driven by delocalization of the lowest energy hole state. The hole delocalization process from the 0D QDash confinement is unfavorable for optical devices based on such tunnel injection structures.
KW  - physics
KW  - surface collisions
KW  - electronic coupling
KW  - transition radiation
KW  - time-resolved photoluminescence
KW  - photoluminescence excitation
KW  - modulation spectroscopy
KW  - quantum dots
KW  - quantum wells
KW  - delocalization
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-181787
VL  - 7
IS  - 1
ER  - 
TY  - JOUR
A1  - Syperek, M.
A1  - Andrzejewski, J.
A1  - Rudno-Rudziński, W.
A1  - Maryński, A.
A1  - Sȩk, G.
A1  - Misiewicz, J.
A1  - Reithmaier, J. P.
A1  - Somers, A.
A1  - Höfling, S.
T1  - The issue of 0D-like ground state isolation in GaAs- and InP-based coupled quantum dots-quantum well systems
JF  - Journal of Physics: Conference Series
N2  - The issue of quantum mechanical coupling between a semiconductor quantum dot and a quantum well is studied in two families of GaAs- and InP- based structures at cryogenic temperatures. It is shown that by tuning the quantum well parameters one can strongly disturb the 0D-character of the coupled system ground state, initially located in a dot. The out-coupling of either an electron or a hole state from the quantum dot confining potential is viewed by a significant elongation of the photoluminescence decay time constant. Band structure calculations show that in the GaAs-based coupled system at its ground state a hole remains isolated in the dot, whereas an electron gets delocalized towards the quantum well. The opposite picture is built for the ground state of a coupled system based on InP.
KW  - quantum mechanical coupling
KW  - quantum well
KW  - semiconductor quantum dot
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-262876
SN  - 1742-6588
SN  - 1742-6596
VL  - 906
IS  - 1
ER  -