Size and temperature effects on electric properties of CdTe/ZnTe quantum rings

Abstract

The electronic properties of CdTe/ZnTe quantum rings (QRs) are investigated as functions of size and temperature using an eight-band strain-dependent k•p Hamiltonian. The size effects of diameter and height on the strain distributions around the QRs are studied. We find that the interband transition energy, defined as the energy difference between the ground electronic and the ground heavy-hole subbands, increases with the increasing QR inner diameter regardless of the temperature, while the interband energy decreases with the increasing QR height. This is attributed to the reduction of subband energies in both the conduction and the valence bands due to the strain effects. Our model, in the framework of the finite element method and the theory of elasticity of solids, shows a good agreement with the temperature-dependent photoluminescence measurement of the interband transition energies.

Ab initio study of structural, electronic and optical properties of ternary CdO 1− x Se x alloys using special quasi-random structures

“…[5] For short and medium wavelengths, Cd-based compounds can also be used as an alternative material. [6,7] The A x B 1−x C types of semiconductors constructed by mixing the elements of AC and BC are scientifically important materials. Their structural, electronic, and optical properties can be incessantly modified by varying the composition x, and thus the range of material properties can be tuned for precise applications.…”

Electronic Raman scattering in double semi-parabolic quantum wells

“…However, few theoretical analyses of the electronic and optical properties associated with the intersubband optical transitions in these structures are presented in scientific literature. [6][7][8][9] Specifically, the nanostructure double quantum well is very interesting as far as the device industry is concerned, and is widely used because it offers the possibility to create an artificial three-level system. Double quantum well (DQW) semiconductor heterostructures are suitable candidates for technological applications such as Raman lasers [10,11] and quantum cascade lasers, [12] as they are suitable candidates for novel application of electron devices.…”

Structure Parameters and Electric Field Effects on Exciton Binding Energies of CdTe/ZnTe Quantum Rings

“…On the other hand, we previously analyzed the electronic and the optical properties of QRs, based on the linear elasticity theory of solids and the eightband k Á p Hamiltonian to determine how three-dimensional strain fields induced around the CdTe/ZnTe QRs affect the conduction and the valence subband energies and the optical gain spectra. 17,18) A precise assessment of the EB energies for various QR structure parameters with and without an electric field is important in understanding the electronic and the optical properties of semiconductor QRs and may help in analyzing the EB energy structures of coupled quantum structures, i.e., quantum molecules, when using them as quantum bits. 19) For example, stacks of (In,Ga)As/GaAs QR molecules have been recently fabricated and the exciton energies were measured using photoluminescence.…”