What is the absorption wavelength of gallium arsenide?
What is the absorption wavelength of gallium arsenide?
The optical absorption of GaAs NWAs for oblique light incidence was also calculated with the optimized structure (D/P = 0.5, D = 180 nm) obtained for normal incident illumination. Figure 4 shows the absorptance of optimized NWAs at wavelength λ = 800 nm for different incident angles.
What is optical absorption semiconductor?
For an indirect band gap semiconductor, like Si, absorption occurs when there is a lattice vibration (phonon) assisting the photon absorption. Optical absorption results in the production of electron-hole pairs. These electron – hole pairs then recombine to produce photons.
What is the refractive index of GaAs?
Refractive index n of GaAs A = 8.950 – empirical coefficient.
What is the absorption coefficient of water?
The absorption coefficient of pure water was found to be 0.00017 cm−1 at 488 nm and 0.00029 cm−1 at 541.5 nm using adiabatic laser calorimetric techniques. These values are in good agreement with the generally accepted long-path transmission spectra of Clarke and James.
What is optical absorption spectroscopy?
6.4. 1.4 Differential optical absorption spectroscopy. Differential optical absorption spectroscopy (DOAS) is a technique that identifies and quantifies trace gas abundances with narrow band absorption structures in the near UV and visible wavelength region in the open atmosphere (e.g., [71]).
What is N in TAUC equation?
Determination of optical band gap The optical band gap of CdS and HgS NPs has been evaluated from the absorption spectrum using the Tauc relation [1] (εhν) = C(hν – Eg)n (1) where C is a constant, ε is molar extinction coefficient, Eg is the average band gap of the material and n depends on the type of transition.
How to calculate the optical absorption of GaAs NWAS?
The optical absorption of GaAs NWAs for oblique light incidence was also calculated with the optimized structure (D /P = 0.5, D = 180 nm) obtained for normal incident illumination. Figure 4 shows the absorptance of optimized NWAs at wavelength λ = 800 nm for different incident angles.
Do geometric parameters affect optical absorption of GaAs nanowire arrays?
In this study, the influence of the geometric parameters on the optical absorption of gallium arsenide [GaAs] nanowire arrays [NWAs] has been systematically analyzed using finite-difference time-domain simulations.
What is the thickness-dependent absorption of GaAs film?
Four lengths, 0.5, 1, 2, and 3 μm, are selected to calculate the thickness-dependent absorption. The absorptance of a 2.2-μm-thick GaAs film is also plotted in the figure for comparison. As seen in this figure, a sharp drop to zero absorption occurs for photon energies smaller than the corresponding bandgap.
What are GaAs nanowires and how do they work?
Among semiconductor nanowires [NWs], gallium arsenide [GaAs] NWs show particular promise due to the superior electrical and optical properties of III to V materials. For example, the GaAs material system features a direct band gap and high absorption coefficient.
