![300k cut off wavelength 300k cut off wavelength](https://pubs.rsc.org/image/article/2021/dt/d1dt03189a/d1dt03189a-f3_hi-res.gif)
The electronic transport parameters calculated here are necessaryįor the design of infrared photo-detectors. That these SL are mid infrared and terahertz detectors. The dispersion relation for electrons, light and heavy holes bands is written as :Ĭos cos(k d ) cos(k d ) 1 [( 1 ) In order to determine the effect of layers thickness and temperature on electronic band structure of these superlattices we have calculated the band structure, band gap energy, the cutoff wavelength and the density of state and we found that SL1 and SL2 are mid infrared detector materials. The later occurred near 20 K in the p type SL1 and near 84 K in SL2 with p type to n type conductivity transition. The calculated density of states and Fermi level energy shows that temperature generated transitions from quasi bidimensional (Q2D) to three dimensional (3D) in the two SL. We calculated the energy of carriers as a function of layers thickness, the ration d1/d2 and the temperature. These studies were done using the envelope function formalism. Laboratory of Condensed Matter Physics and Nanomaterials for Renewable Energy Department of Physics Faculty of Sciences Ibn Zohr UniversityĪbstract We report here the effect of layers thickness and temperature on electronic transport of nanostructure by calculation of band structure of two superlattices SL1 InAs(d1)/Gasb(d2) of type II and SL2 HgTe/CdTe of type III for infrared detection application.
![300k cut off wavelength 300k cut off wavelength](https://i.etsystatic.com/7059968/r/il/a78edf/2660293552/il_794xN.2660293552_hgp4.jpg)
Nassima Benchtaber, Abdelhakim Nafidi, Samir Melkoud, Meriem Benaadad, Driss Barkissy We observe very low knee frequencies (below 10Hz) in their noise spectra.Effect of Layers Thickness and Temperature on Electronic Transport of Nanostructures Infrared Detectors The detectivities of the second batch devices at 77K were in the range of 10 8 to 10 10 cmHz½/W and showed frequency dependence because the noise had frequency dependence. The electrical properties showed higher R 0 A values (approximately 8 ohm-cm 2 ). A second batch of devices was annealed at 120☌ for 1 hr or 5 min. This was interpreted to be due to the formation of a junction near the boundary of the superlattice and a high carrier concentration region of HgCdTe alloy. A first batch of devices annealed at 150☌ or 180☌ for 1 hr after the deposition of 50Å thick gold films showed relatively low R 0 A values (approximately 0.3 ohm-cm 2 ). The cut-off wavelengths of another sample were approximately 14 and 18 ॖm at 77 and 40K, respectively, as determined by optical absorption and spectral response measurements. The superlattice period of one sample was 98.3Å according to its x-ray diffraction profile, very close the intended 98.5Å for a 48.5Å HgTe/50.Å Hg 0.05 Cd 0.95 Te superlattice. P + -v-N + structures with HgTe/CdTe superlattice absorber regions were grown by MBE to give cut-off wavelengths in the very long wavelength infrared (14 ॖm and longer) at temperatures below 80 K. Fabrication and characteristics of nonequilibrium VLWIR detectors with HgTe/CdTe superlattice active regions Fabrication and characteristics of nonequilibrium VLWIR detectors with HgTe/CdTe superlattice.