Binding energies of excitons in II–VI compound‐semiconductor based quantum well structures

Abstract

We present a brief description of the calculation of the variation of the binding energy of the heavy-hole exciton as a function of well width in quantum well structures composed of II-VI compound semiconductors including the effects of exciton-optical phonon interaction as formulated by Pollmann and Büttner [J. Pollmann and H. Büttner, Phys. Rev. B 16, 4480 (1977)], and of particle masses and dielectric mismatches between the well and the barrier layers. We compare the results of our calculations with the available experimental data in ZnSe/MgS, ZnSe/Mg 0.15 Zn 0.85 Se, and ZnS/Mg 0.19 Zn 0.81 S quantum well structures and find a good agreement.

Effect of Exciton-Longitudinal Optical Phonon Interaction οn Exciton Binding Energies in ZnS/MgxBeyZn1-x-yS Quantum Wells

“…For comparison of the theoretical results with the experimen-tal results, the heavy-and light-hole exciton binding energies measured for ZnS/Mg x Zn 1−x S SQWs at x = 0.19 [12] are also plotted. The bandgap discontinuity ∆E in ZnS/Mg x Be y Zn 1−x−y S SQWs for x = 0.14 is estimated to be 178.8 meV, whereas that in ZnS/Mg x Zn 1−x S SQWs for x = 0.19 is estimated to be 174.0 meV [7].…”

“…44.0 [7] TABLE II Increase in the maximum heavy-and light-hole exciton binding energies [meV]. The changes in the binding energies of the heavy-and light-hole excitons with L w are essentially similar.…”

“…Senger and Bajaj reported that the exciton binding energies calcu- * corresponding author; e-mail: ycd1ngt@yahoo.co.jp lated for QWs increase when the effect of the exciton-LO phonon interaction is considered [6]. They calculated the exciton binding energies for various II-VI semiconductor QWs (Zn-, Cd-, and Mg-containing II-VI semiconductor QWs) by considering the effect of the exciton-LO phonon interaction [6,7]. The results of their calculations showed that the effect of exciton-LO phonon interaction on electron-hole Coulomb interactions plays an important role in increasing the exciton binding energy in II-VI semiconductor QWs [6,7].…”

Temperature changes in the function of the shape inherent to the band of exciton absorption in nanofilm of layered semiconductor

“…Spatial confinement of quasi-particles in low-dimensional structures cause additional quantization of their motion characteristics, which is pronounced in experimentally observed changes in their optical properties, including those in the excitonic range of the spectrum [ 6 3  ]. Theoretical investigations of exciton states in nanostructures with single quantum wells (QW) were performed by many authors with various methods and approaches (see, for instance, [10][11][12][13]), however, the nanostructures based on layered crystals were not considered in them.…”

Temperature changes of the exciton transition energy in lead di-iodide nanofilms

“…Theoretical investigations of exciton states in nanostructures with single quantum wells (QW) were performed by many authors that used various methods and approaches (see, for instance, [12][13][14][15]), however, the nanostructures based on lead di-iodide have not been considered there.…”