Carrier dynamics and activation energy of CdTe quantum dots in a CdxZn1−xTe quantum well

Abstract

We investigate the optical properties of CdTe quantum dots (QDs) in a Cd0.3Zn0.7Te quantum well (QW) grown on GaAs (100) substrates. Carrier dynamics of CdTe/ZnTe QDs and quantum dots-in-a-well (DWELL) structure is studied using time-resolved photoluminescence (PL) measurements, which show the longer exciton lifetime of the DWELL structure. The activation energy of the electrons confined in the DWELL structure, as obtained from the temperature-dependent PL spectra, was also higher than that of electrons confined in the CdTe/ZnTe QDs. This behavior is attributed to the better capture of carriers into QDs within the surrounding QW.

Spontaneous and stimulated emission dynamics of PbS quantum dots in a glass matrix

“…Attention should be paid to the quenching track of PL-I I (or I ), namely, an approximately linear decrease rather than a slow (or exponential-like) decay 26 below ∼100 K followed by a discontinuity (or abnormal hop) as the temperature increases above 100 K. Shown in Fig. 3(b) is the PL-I I in an Arrhenius plot from which we can see that the PL-I I develops as a two-stage process including a slow decrease from 20 K and a fast one above ∼100 K. The slopes of these two parts can be evaluated from [38][39][40][41][42] …”

Carrier dynamics and activation energy of CdTe/ZnTe nanostructures with different CdTe thicknesses

“…The excitonic properties of II-VI semiconductor nanostructures, as compared with conventional III-V semiconductor nanostructures, are enhanced because of the larger exciton binding energy in the materials. As typical II-VI nanostructures, CdTe/ZnTe nanostructures are characterized by large excitonic binding energies and are of great interest because of their potential applications in optoelectronic devices operating in the green spectral range [9,10]. In addition, the study of carrier dynamics in the semiconductor nanostructures not only offers a convenient means to clarify their structure but also provides useful information for applying them to optoelectronic devices.…”