Topic
Potential well
About: Potential well is a research topic. Over the lifetime, 1430 publications have been published within this topic receiving 30812 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, the energy difference between the states of the lowest doublet in a well with a V-shaped potential is calculated variationally using a two-band tight-binding model.
Abstract: The valley splitting (energy difference between the states of the lowest doublet) in strained silicon quantum wells with a V-shaped potential is calculated variationally using a two-band tight-binding model. The approximation is valid for a moderately long (approximately 5.5–13.5nm) quantum well with a V-shaped potential which can be produced by a realistic delta-doping on the order of nd≈1012cm−2. The splitting versus applied field (steepness of the V-shaped potential) curves show interesting behavior: a single minimum and for some doublets, a parity reversal as the field is increased. These characteristics are explained through an analysis of the variational wave function and energy functional.
20 citations
TL;DR: Through photoluminescence (PL) studies, a weak UV emission and strong red wavelength emissions were received and discussed on the basis of sulfur vacancies and this red emission was dealt in terms of d-electrons transition between host and dopant ions.
20 citations
TL;DR: In this paper, photoacoustic (PA), photoluminescence (PL), and atomic force microscopy (AFM) techniques were applied on porous silicon (PS) layers to study the influence of chemical etching by low-concentration hydrofluoric acid.
Abstract: We applied photoacoustic (PA), photoluminescence (PL), photoluminescence excitation (PLE), and atomic force microscopy (AFM) techniques on porous silicon (PS) layers to study the influence of chemical etching by low-concentration hydrofluoric acid. The chemical etching reveals the formation of PS layers of small dimensions by AFM observations, indicating the possibility of a strong quantum confinement effect. PA spectroscopy is useful to obtain the optical absorption characteristic for strongly scattering media such as PS and it helps to confirm the above speculation by indicating the blueshift of the fundamental absorption edge for the PS layer with chemical etching. PL spectroscopy also confirms the possibility of a quantum confinement effect by revealing the strong intensity and blueshift for the PS layer with chemical etching. PLE measurements suggest that the site for the radiative processes is different from that for the recombination of carriers and the PL of PS layers were dominated only by small ...
20 citations
TL;DR: In this article, the optical gains of ultrathin Si(001) quantum wells are calculated from first principles, and they are found to be positive because of an intrinsic quantum confinement effect.
Abstract: Optical gains of ultrathin Si(001) quantum wells are calculated from first principles, and found to be positive because of an intrinsic quantum confinement effect. The gain of the ultrathin silicon film is comparable to that of the bulk GaAs if the carrier density is large enough. The impact of surface structure of the silicon film on the efficiency of light emission is also investigated and we found that ${\text{SiO}}_{2}$ crystal that forms a strainless connection with a Si(001) surface such as quartz enhances optical gain.
20 citations
TL;DR: In this article, the authors demonstrate the synthesis of copper selenide quantum dots (QDs) by element directed, inexpensive, straight forward wet chemical method which is free from any surfactant or template.
Abstract: We demonstrate the synthesis of copper selenide quantum dots (QDs) by element directed, inexpensive, straight forward wet chemical method which is free from any surfactant or template. Copper selenide QDs have been synthesized by elemental copper and selenium in the presence of ethylene glycol, hydrazine hydrate, and a defined amount of water at 70 °C within 8 h. The product is in strong quantum confinement regime, phase analysis, purity and morphology of the product has been well studied by X-ray diffraction (XRD), UV–Visible spectroscopy (UV–Vis), Photo-luminescent spectroscopy (PL), Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), High resolution transmission electron microscopy (HRTEM), and by Atomic force microscopy (AFM) techniques. The absorption and photoluminescence studies display large “blue shift”. TEM and HRTEM analyses revealed that the QDs diameters are in the range 2–5 nm. Due to the quantum confinement effect copper selenide QDs could be potential building blocks to construct functional devices and solar cell. The possible mechanism is also discussed.
20 citations