Band gap energy and valence band splitting of p-CdIn2Te4 crystal by photocurrent spectroscopy

2004 ◽  
Vol 95 (8) ◽  
pp. 4042-4045 ◽  
Author(s):  
S. H. You ◽  
K. J. Hong ◽  
T. S. Jeong ◽  
C. J. Youn ◽  
J. S. Park ◽  
...  
2018 ◽  
Vol 1 (02) ◽  
pp. 54-59
Author(s):  
Agus Ismangil ◽  
Teguh Puja Negara

One of the studies that recently attracted the attention of physicists is research on ferroelectric material because this material is very promising for the development of new generation devices in connection with the unique properties it has. Ferroelectric materials, especially those based on a mixture of lithium tantalite (LiTaO3), are expected to be applied to the infrared sensor. Lithium tantalate (LiTaO3) is a ferroelectric material that is unique in terms of pyroelectric and piezoelectric properties that are integrated with good mechanical and chemical stability. Therefore LiTaO3 is often used for several applications such as electro-optical modulators and pyroelectric detectors. LiTaO3 is a non-hygroscopic crystal, colorless, soluble in water, has a high transmission rate and does not easily damage its optical properties. LiTaO3 is a material that has a high dielectric constant and a high load storage capacity. This research has succeeded in determining the band gap energy of the LiTaO3 film in the rubidium chamber obtained in the range of values 2.02-2.98 eV as shown in figure 4. The LiTaO3 film after the annealing process at a temperature of 650 oC, has the highest band gap energy of 2.98 eV. Large energy is needed on the electrons to be excited from the valence band to the conduction band. Whereas in the LiTaO3 film after an annealing process of 800 oC, the band gap energy obtained is 2.02 eV. This makes it easier for electrons to be excited from the valence band to the conduction band because the energy needed is not too large.


2021 ◽  
Vol 32 (2) ◽  
pp. 1-5
Author(s):  
Agus Ismangil ◽  
Fatimah Arofiati Noor ◽  
Toto Winata

Chemical solution deposition (CSD) is a technique for making a film by keeping synthetic arrangements on the outer layer of the substrate. The outcomes show that the band gap energy of the LiTaO3 film is 1 eV. Electrons are more effectively invigorated to the valence band than to the conduction band on the grounds that the energy required is not excessively huge. Niobium-doped LiTaO3 film has a band gap energy of 1.15 eV. A large amount of energy is needed for electrons to be energized from the valence band to the conduction band. The rubidium-doped LiTaO3 film has a band gap energy of 1.30 eV.


1995 ◽  
Vol 67 (16) ◽  
pp. 2347-2349 ◽  
Author(s):  
P. Ernst ◽  
C. Geng ◽  
F. Scholz ◽  
H. Schweizer ◽  
Yong Zhang ◽  
...  

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
D. P. Samajdar ◽  
S. Dhar

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.


1998 ◽  
Vol 83 (11) ◽  
pp. 6196-6198 ◽  
Author(s):  
R. Wirth ◽  
H. Seitz ◽  
M. Geiger ◽  
J. Porsche ◽  
F. Scholz ◽  
...  

2020 ◽  
Vol 92 (2) ◽  
pp. 20402
Author(s):  
Kaoutar Benthami ◽  
Mai ME. Barakat ◽  
Samir A. Nouh

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.


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