PRESSURE—DEPENDENT MAGNETO—OPTIC MEASUREMENTS IN STRAINED—LAYER SUPERLATTICES AT LOW TEMPERATURES

1985 ◽  
Vol 56 ◽  
Author(s):  
E. D. JONES ◽  
J. E. SCHIRBER ◽  
I. J. FRITZ ◽  
P. L. GOURLEY ◽  
R. M. BIEFELD ◽  
...  
Keyword(s):  
Band Gap Energy ◽  
Light Hole ◽  
Strained Layer ◽  
Pressure Coefficients ◽  
Gap Energy ◽  
Effective Masses ◽  
Strained Layer Superlattices ◽  
Experimental Pressure ◽  
Plane Light ◽  
Magneto Optic

AbstractMagneto—optic studies on InGaAs/GaAs and GaAs/GaPAs strained—layer superlattices are used to determine the in—plane light—hole valence—band effective masses. Also, hydrostatic pressure—dependent magneto—optic studies have been performed on these samples for magnetic fields up to 65 kG andpressures to 4 kbar in the temperature range of 1.6 - 4 K. The experimental pressure coefficients of the band—gap energy and the effective mass in the InGaAs/GaAsSLS structures were determined.

Magneto-optic determination of the light-hole effective masses in InGaAs/GaAs strained-layer superlattices

1985 ◽  
Vol 55 (6) ◽  
pp. 525-527 ◽  
Author(s):  
E.D. Jones ◽  
H. Ackermann ◽  
J.E. Schirber ◽  
T.J. Drummond ◽  
L.R. Dawson ◽  
...  
Keyword(s):  
Light Hole ◽  
Strained Layer ◽  
Effective Masses ◽  
Strained Layer Superlattices ◽  
Magneto Optic

Magneto‐optic determinations of the pressure dependence of band‐gap energies and effective masses in strained‐layer superlattices

1985 ◽  
Vol 47 (5) ◽  
pp. 492-494 ◽  
Author(s):  
E. D. Jones ◽  
H. Ackermann ◽  
J. E. Schirber ◽  
T. J. Drummond ◽  
L. R. Dawson ◽  
...  
Keyword(s):  
Band Gap ◽  
Pressure Dependence ◽  
Strained Layer ◽  
Effective Masses ◽  
Strained Layer Superlattices ◽  
Magneto Optic

Light‐hole conduction in InGaAs/GaAs strained‐layer superlattices

1985 ◽  
Vol 46 (2) ◽  
pp. 187-189 ◽  
Author(s):  
J. E. Schirber ◽  
I. J. Fritz ◽  
L. R. Dawson
Keyword(s):  
Light Hole ◽  
Strained Layer ◽  
Hole Conduction ◽  
Strained Layer Superlattices

scholarly journals Valence Band Structure ofInAs1-xBixandInSb1-xBixAlloy Semiconductors Calculated Using Valence Band Anticrossing Model

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
D. P. Samajdar ◽  
S. Dhar
Keyword(s):  
Experimental Data ◽  
Band Gap ◽  
Valence Band ◽  
Band Gap Energy ◽  
Light Hole ◽  
Spin Orbit ◽  
Valence Band Structure ◽  
Gap Energy ◽  
Valence Band Anticrossing ◽  
Band Anticrossing

The valence band anticrossing model has been used to calculate the heavy/light hole and spin-orbit split-off energies inInAs1-xBixandInSb1-xBixalloy systems. It is found that both the heavy/light hole, and spin-orbit splitE+levels move upwards in energy with an increase in Bi content in the alloy, whereas the splitE−energy for the holes shows a reverse trend. The model is also used to calculate the reduction of band gap energy with an increase in Bi mole fraction. The calculated values of band gap variation agree well with the available experimental data.

Modification of optical properties of PC-PBT/Cr2O3 and PC-PBT/CdS nanocomposites by gamma irradiation

2020 ◽  
Vol 92 (2) ◽  
pp. 20402
Author(s):  
Kaoutar Benthami ◽  
Mai ME. Barakat ◽  
Samir A. Nouh
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Band Gap ◽  
Color Difference ◽  
Band Gap Energy ◽  
Polybutylene Terephthalate ◽  
Γ Irradiation ◽  
Gap Energy ◽  
Vis Spectroscopy ◽  
Oxygen Atoms

Nanocomposite (NCP) films of polycarbonate-polybutylene terephthalate (PC-PBT) blend as a host material to Cr2O3 and CdS nanoparticles (NPs) were fabricated by both thermolysis and casting techniques. Samples from the PC-PBT/Cr2O3 and PC-PBT/CdS NCPs were irradiated using different doses (20–110 kGy) of γ radiation. The induced modifications in the optical properties of the γ irradiated NCPs have been studied as a function of γ dose using UV Vis spectroscopy and CIE color difference method. Optical dielectric loss and Tauc's model were used to estimate the optical band gaps of the NCP films and to identify the types of electronic transition. The value of optical band gap energy of PC-PBT/Cr2O3 NCP was reduced from 3.23 to 3.06 upon γ irradiation up to 110 kGy, while it decreased from 4.26 to 4.14 eV for PC-PBT/CdS NCP, indicating the growth of disordered phase in both NCPs. This was accompanied by a rise in the refractive index for both the PC-PBT/Cr2O3 and PC-PBT/CdS NCP films, leading to an enhancement in their isotropic nature. The Cr2O3 NPs were found to be more effective in changing the band gap energy and refractive index due to the presence of excess oxygen atoms that help with the oxygen atoms of the carbonyl group in increasing the chance of covalent bonds formation between the NPs and the PC-PBT blend. Moreover, the color intensity, ΔE has been computed; results show that both the two synthesized NCPs have a response to color alteration by γ irradiation, but the PC-PBT/Cr2O3 has a more response since the values of ΔE achieved a significant color difference >5 which is an acceptable match in commercial reproduction on printing presses. According to the resulting enhancement in the optical characteristics of the developed NCPs, they can be a suitable candidate as activate materials in optoelectronic devices, or shielding sheets for solar cells.

Si-Ge STRAINED LAYER SUPERLATTICES

1987 ◽  
Vol 48 (C5) ◽  
pp. C5-321-C5-327 ◽  
Author(s):  
H. BRUGGER ◽  
G. ABSTREITER
Keyword(s):  
Strained Layer ◽  
Strained Layer Superlattices

Stability Investigation in the Optical Properties of Thermally Evaporated Ge5Se95-x Znx Thin Films

2015 ◽  
Vol 7 (3) ◽  
pp. 1923-1930
Author(s):  
Austine Amukayia Mulama ◽  
Julius Mwakondo Mwabora ◽  
Andrew Odhiambo Oduor ◽  
Cosmas Mulwa Muiva ◽  
Boniface Muthoka ◽  
...  
Keyword(s):  
Thin Films ◽  
Band Gap ◽  
Optical Band Gap ◽  
Thermal Evaporation ◽  
Optical Transition ◽  
Bulk Material ◽  
Band Gap Energy ◽  
Optical Absorbance ◽  
Gap Energy ◽  
Constituent Elements

 Selenium-based chalcogenides are useful in telecommunication devices like infrared optics and threshold switching devices. The investigated system of Ge5Se95-xZnx (0.0 ≤ x ≤ 4 at.%) has been prepared from high purity constituent elements. Thin films from the bulk material were deposited by vacuum thermal evaporation. Optical absorbance measurements have been performed on the as-deposited thin films using transmission spectra. The allowed optical transition was found to be indirect and the corresponding band gap energy determined. The variation of optical band gap energy with the average coordination number has also been investigated based on the chemical bonding between the constituents and the rigidity behaviour of the system’s network.

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