Wide quantum dots were fabricated from multiple quantum-well (MQW) structures based on Zn
1−
x
Mn
x
Te/ZnTe (
x = 0.076) dilute magnetic semiconductors and were investigated via photoluminescence ...(PL) in a magnetic field. Calculations taking into account the strain in the two types of structure enabled the PL transitions to be identified and show that the dominant emission in the MQWs is from heavy-hole (hh) excitons whereas in the quantum dots, the removal of the strain in the barrier layers generates a large biaxial tensile strain in the quantum wells which shifts the light-hole (lh) exciton to lower energy than the hh exciton. The lh exciton σ
+ transition is virtually independent of magnetic field whilst the hh exciton is field-dependent. Thus, at fields of 1–2 T, the hh exciton σ
+ transition again becomes the lowest-energy transition of the quantum dots. These observations are described by a model with a chemical valence band offset of 30% for Zn
1−
x
J:Mn
x
Te/ZnTe.
J. Cryst. Growth 184/185 (1998) 325-329 Wide quantum dots were fabricated from multiple quantum well structures based
on Zn_{1-x}Mn_xTe/ZnTe (x = 0.076) dilute magnetic semiconductors and were
...investigated via photoluminescence (PL) in a magnetic field. Calculations
taking into account the strain in the two types of structure enabled the PL
transitions to be identified and show that the dominant emission in the MQWs is
from heavy-hole (hh) excitons whereas in the quantum dots, the removal of the
strain in the barrier layers generates a large biaxial tensile strain in the
quantum wells which shifts the light-hole (lh) exciton to lower energy than the
hh exciton. The lh exciton sigma^+ transition is virtually independent of
magnetic field whilst the hh exciton is field-dependent. Thus, at fields of 1
to 2 Tesla, the hh exciton sigma^+ transition again becomes the lowest energy
transition of the quantum dots. These observations are described by a model
with a chemical valence band offset of 30% for Zn_{1-x}Mn_xTe/ZnTe.
Wide quantum dots were fabricated from multiple quantum well structures based on Zn_{1-x}Mn_xTe/ZnTe (x = 0.076) dilute magnetic semiconductors and were investigated via photoluminescence (PL) in a ...magnetic field. Calculations taking into account the strain in the two types of structure enabled the PL transitions to be identified and show that the dominant emission in the MQWs is from heavy-hole (hh) excitons whereas in the quantum dots, the removal of the strain in the barrier layers generates a large biaxial tensile strain in the quantum wells which shifts the light-hole (lh) exciton to lower energy than the hh exciton. The lh exciton sigma^+ transition is virtually independent of magnetic field whilst the hh exciton is field-dependent. Thus, at fields of 1 to 2 Tesla, the hh exciton sigma^+ transition again becomes the lowest energy transition of the quantum dots. These observations are described by a model with a chemical valence band offset of 30% for Zn_{1-x}Mn_xTe/ZnTe.
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