Compressive strain induced heavy hole and light hole splitting of Zn1−xCdxSe epilayers grown by molecular beam epitaxy

Yang, C. S.; Hsieh, Yi‐Ting; Kuo, M. C.; Tseng, P. Y.; Yeh, Zih-Ming; Chiu, Kuan−Cheng; Shen, Ji‐Lin; Chu, Amy H. M.; Chou, Wu–Ching; Lan, Wen−How

doi:10.1016/s0254-0584(01)00585-5

Cited by 16 publications

(9 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here we attributed the splitting of the first excitonic peak during the shell growth to the anisotropic pressure of the CdS shell on the CdSe cores, which induced an additional splitting between the heavy hole and light hole bands. Similar splitting was reported for epitaxially grown quantum dots (see, for example, refs and ). In the case of CdSe/CdS core/shell NCs, with a lattice mismatch about 3.8%, we used a cylinder-in-a-cylinder geometry to model the anisotropic pressure in our dot-in-plate system, and we neglected the amount of CdS grown along the c axis.…”

Section: Resultssupporting

confidence: 84%

Colloidal CdSe/CdS Dot-in-Plate Nanocrystals with 2D-Polarized Emission

et al. 2012

View full text Add to dashboard Cite

We report the synthesis and properties of a novel class of nanocrystals with mixed dimensionality: a dot-in-plate core/shell nanostructure. This system was synthesized by growing a flat, disk-shaped, CdS shell on spherical CdSe cores. The anisotropic pressure induced by the shell drastically splits the first exciton fine structure in two: the "heavy hole" and "light hole" states become separated by up to 65 meV. As a result, these nanocrystals exhibit an emission strongly polarized in two dimensions, in the plane perpendicular to the wurtzite crystal c axis. We use polarization measurements on single nanocrystals and ensemble anisotropy studies to confirm the nature and position of the excitonic energy levels. These nanocrystals orient spontaneously when evaporated on a substrate, enabling a precise control of the orientation of their emission dipole.

show abstract

Section: Resultssupporting

confidence: 84%

Colloidal CdSe/CdS Dot-in-Plate Nanocrystals with 2D-Polarized Emission

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Figure 2(h) shows the schematic band diagram near the À point of the strained GaAs. 25,26) The in-plane tensile strain not only reduces the band gap energy, but also induces the splitting of heavy-hole (solid) and light-hole (dot) bands. The transition energies from the conduction band to the heavy-and lighthole bands are expressed as E hh and E lh , respectively, and labeled in the CL spectra.…”

Section: Resultsmentioning

confidence: 99%

Optical Studies of GaAs Nanowires Grown on Trenched Si(001) Substrate by Cathodoluminescence

Lee¹,

Chien²,

Fan³

et al. 2012

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

The strains in GaAs nanowires, which were grown from 1700-to 80-nm-wide trenches on the Si(001) wafer with SiO 2 masks, were investigated by cathodoluminescence. For 1700-to 500-nm-wide trenches, the in-plane tensile strain at 15 K decreases with the decreasing trench width. The strain increases abruptly when the trench width is 300 nm, and then decreases as the trench width is further decreased. The results revealed that the stress induced by the SiO 2 sidewalls dominates when the width is less than the depth of the trench. This approach provides an effective technique to measure the strain of a single nanowire and helps for the demonstration of selectively-grown GaAs with a designed strain.

show abstract

“…Zinc sulfide and zinc selenide at the nanoscale regime having beneficial optical and electrical properties; therefore, it is used in different fields such as mid-infrared laser applications, photocatalysts, and sensors [10][11][12]. The formation of ternary alloys of varying concentrations offers the possibility of obtaining a material having the ability to regulate optical and electrical properties [13]. Ternary alloys from (Zn, S, and Se) atoms are considered as a promising material in the construction of biomedical labels, lenses and optically controlled switches due to high occupied molecular orbital (HOMO), lower unoccupied molecular orbital (LUMO) levels, and lattice parameters variation with the compositions [14,15].…”

Section: Introductionmentioning

confidence: 99%

Analysis of electronic, Raman and UV-vis spectra for Zn11Se11, Zn11S11, and ternary alloys Zn11SnSe11-n(n= 1-11) A DFT/TDDFT study.

2020

View full text Add to dashboard Cite

Zn 11 Se 11 , Zn 11 S 11 , and ternary alloys from Zn 11 S n Se 11-n (n = 1-11), with cubic structures represented by nanostructures called tetramantane, have been studied theoretically by investigating the electronic properties, Raman and UV-vis spectra. LUMO and HOMO levels were observed to change with the number of the sulfur atoms. The (HOMO-LUMO) gap for Zn 11 Se 11 (2.377205eV) increased with the sulfur atoms. Zn 11 S 8 Se 3 have an energy gap (3.061305eV) less than others ternary alloys. The calculated energy gap of Zn 11 S 11 (3.597374eV) is in a high agreement with experimental value (3.6 eV). Raman spectra for ternary alloys Zn 11 S n Se 11-n content peaks result from the connection of (Zn 11 Se 11 +Zn 11 S 11) peaks, Zn 11 Se 11 has peak at 260.42 cm-1 shifts from the experimental value by a small deviasion which is produced due to the confinement effect. UV-vis spectra for ternary alloys shifted to a higher energy level with the increase in the number of sulfur atoms and dramatically close to Zn 11 S 11 UV-vis spectrum except Zn 11 S 8 Se 3 has λ max at 342 nm. These nanostructures are suitable to be used in different applications such as lenses, photoelectronic devices, solar energy, and biosensors. DFT/TDDFT at the B3LYP level with SDD basis functions is used. All the calculations are completed using the Gaussian 09 program.

show abstract

Compressive strain induced heavy hole and light hole splitting of Zn1−xCdxSe epilayers grown by molecular beam epitaxy

Cited by 16 publications

References 18 publications

Colloidal CdSe/CdS Dot-in-Plate Nanocrystals with 2D-Polarized Emission

Colloidal CdSe/CdS Dot-in-Plate Nanocrystals with 2D-Polarized Emission

Optical Studies of GaAs Nanowires Grown on Trenched Si(001) Substrate by Cathodoluminescence

Analysis of electronic, Raman and UV-vis spectra for Zn11Se11, Zn11S11, and ternary alloys Zn11SnSe11-n(n= 1-11) A DFT/TDDFT study.

Contact Info

Product

Resources

About