Hidden resonant excitation of photoluminescence in bilayer arrays of InAs/GaAs quantum dots

Abstract

Photoluminescence of self-assembled InAs/GaAs quantum dots excited by ultraintensive femtosecond laser Photoluminescence from self-assembled long-wavelength InAs/GaAs quantum dots under pressure J. Appl. Phys. 95, 933 (2004); 10.1063/1.1635988Temperature dependence of intersublevel absorption in InAs/GaAs self-assembled quantum dots

Interdot carrier transfer in asymmetric bilayer InAs∕GaAs quantum dot structures

“…By using different InAs deposition rates, growth temperatures, or annealing times for the specific layers, vertically stacked QD layers with differently sized dots, but uniform size distribution in each layer, have been achieved. [7][8][9][10][11][12][13] In this case, the spacer thickness between the QD layers represents a very important parameter. In this letter, the population of larger-sized dots ͑LQD͒ affected by carriers from smaller-sized dots ͑SQD͒ is monitored and transient PL is used as the main tool for the visualization of this inter-QD carrier transfer.…”

“…This is due to additional deposition as well as to the influence of the strain field from the seed layer. 5,10,11 Thus, we obtain two vertically correlated QD layers with different sized dots in each layer. Such a system has been called an ''asymmetric QD pair'' ͑AQDP͒ in analogy with extensive work on an asymmetric double quantum-well ͑ADQW͒ system.…”

Nonresonant tunneling carrier transfer in bilayer asymmetricInAs∕GaAsquantum dots

“…5͑b͒ we used d sp ef f by taking into account the average dot height of ϳ4 nm determined from STM images of uncapped single layer 1.8 ML samples. 23 As can be seen in Fig. 5͑b͒, the transient data for the InAlAs/ GaAs/ InAs AQDP 19 ͑the only electron tunneling time T directly measured in AQDP to our knowledge͒ and the ADQW 20,21 ͑one of the several transient measurements with similar results͒ indicate a difference in tunneling time by one order-of-magnitude.…”

Cap layer induced stress in InAs∕(Al)GaAs quantum dots

“…Usually, other groups take 1 nm as the finest statistical measuring error. 18,19 Such error is far beyond the actual variarion of dot height after being capped by GaAs. In other words, the theoretical calculations indicate that the 1-nm change of dot height leads to more than 40-meV shift of PL peak energies which is the difference between sample A and B.…”