Optical properties of CdTe∕ZnTe quantum dots sandwiched between two quantum wells with ZnTe separation barriers

2006 ◽  
Vol 89 (18) ◽  
pp. 181929 ◽  
Author(s):  
H. S. Lee ◽  
H. L. Park ◽  
T. W. Kim
2004 ◽  
Vol 831 ◽  
Author(s):  
Sławomir P. Łepkowski ◽  
Grzegorz Jurczak ◽  
Paweł Dłużewski ◽  
Tadeusz Suski

ABSTRACTWe theoretically investigate elastic, piezoelectric and optical properties of wurtzite GaN/AlN quantum dots, having hexagonal pyramid-shape, stacked in a multilayer. We show that the strain existing in quantum dots and barriers depends significantly on the distance between the dots i.e. on the width of AlN barriers. For typical QDs, having the base diameter of 19.5nm, the drop of the electrostatic potential in the quantum dot region slightly decreases with decreasing of the barrier width. This decrease is however much smaller for QDs than for superlattice of GaN/AlGaN quantum wells, with thickness similar to the height of QDs. Consequently, the band-to-band transition energies in the vertically correlated GaN/AlN QDs show unexpected, rather weak dependence on the width of AlN barriers. Increasing the QD base diameter leads to stronger decreasing dependence of the band-to-band transition energies vs. the width of AlN barriers, similar to that observed for superlattieces of QWs.


2006 ◽  
Vol 73 (24) ◽  
Author(s):  
M. Funato ◽  
K. Omae ◽  
Y. Kawakami ◽  
Sg. Fujita ◽  
C. Bradford ◽  
...  

2019 ◽  
Vol 1410 ◽  
pp. 012157 ◽  
Author(s):  
A S Dragunova ◽  
N V Kryzhanovskaya ◽  
M V Maximov ◽  
S A Mintairov ◽  
N A Kalyuzhnyy ◽  
...  

2006 ◽  
Vol 959 ◽  
Author(s):  
Shengkun Zhang ◽  
Xuecong Zhou ◽  
Aidong Shen ◽  
Wubao Wang ◽  
Robert Alfano ◽  
...  

ABSTRACTIn this research, interband and intersubband optical properties of heavily doped n-type CdSe quantum dots were investigated by temperature dependent photoluminescence (PL) spectroscopy, picosecond time-resolved PL spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Two doped and one undoped CdSe quantum dot samples with multiple QD layers were grown over ZnCdMgSe barrier layers on InP (001) substrate by molecular beam epitaxy. Heavy doping leads to decreasing of activation energy of nonradiative recombination centers, however, does not affect the luminescence efficiency of doped quantum wells. Time resolved PL experiments show that the PL decay times of the doped samples have weak dependence on well width and are much longer than that of the undoped sample. The two doped CdSe QD samples show strong Intersubband IR absorption that peaked at 2.54 μm, 2.69 μm and 3.51 μm. The ISB absorption is found to be strongly polarization dependent due to the large size of the QDs.


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