Probe of the Band Structure of MBE Grown p-Type InMnAs at Ultrahigh Magnetic Fields

We present a theoretical and experimental study on electronic and magneto-optical properties of p-type paramagnetic InMnAs dilute magnetic semiconductor (DMS) alloys in ultrahigh (> 100 T) external magnetic fields (B). Theoretical calculations are based on an 8-band Pidgeon–Brown model which is generalized to include the wavevector dependence of the electronic states along B as well as s–d and p–d exchange interactions with localized Mn d-electrons. The spin-dependent electronic structure as a function of Mn doping is computed and the dependence of the valence band structure on parameters such as the sp–d exchange interaction strength and effective masses in paramagnetic p- InMnAs alloys are examined. The cyclotron resonance (CR) and magneto-optical properties of InMnAs are calculated using Fermi's golden rule. Two strong CR peaks are observed in p-type InMnAs alloys which correspond to the transitions within either heavy-hole (HH) or light-hole (LH) Landau levels. Furthermore, we also observed strong resonance absorption for electron-active polarization which can occur in p-type semiconductors originating from transitions between the light and heavy hole Landau levels.

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Exploration on electronic and optical properties of two-dimensional GaN-doped with Be, Mg, Zn

International Journal of Modern Physics B ◽

10.1142/s0217979220501957 ◽

2020 ◽

Vol 34 (20) ◽

pp. 2050195

Author(s):

Gang Li ◽

Lei Liu ◽

Jian Tian

Keyword(s):

Optical Properties ◽

Band Structure ◽

Density Of States ◽

First Principles ◽

High Energy ◽

Low Energy ◽

Two Dimensional ◽

Electronic And Optical Properties ◽

Type Semiconductor ◽

P Type

To explore the variation on p-type-doped two-dimensional GaN, we calculate electronic and optical properties of buckled two-dimensional GaN-doped with p-type doping elements including Be, Mg and Zn atom by using first-principles. The results indicate that doping process of two-dimensional GaN after Be is most easily compared with Mg- and Zn-doped models. Band of doped two-dimensional GaN moves toward high energy end and it becomes a p-type semiconductor from the results of band structure and density of states, which may be caused by orbitals hybridization from dopants. Band gap and work function of doped two-dimensional GaN are both declined, which is beneficial for escape of electrons. Analysis of optical properties shows that they are sensitive and adjustable in doped two-dimensional GaN. Doping of Be, Mg and Zn atoms would have an important effect on optical characteristics of two-dimensional GaN at low-energy region.

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Ab-initio Calculations of Structural Parameters, Band Structure and Density of States of Delafossite CuAlO

10.21826/viiiseedmol2020143 ◽

2020 ◽

Author(s):

A.F. Carlos-Chilo ◽

F.F.H. Aragon ◽

L. Villegas-Lelovsky ◽

D. G. Pacheco-Salazar

Keyword(s):

Band Structure ◽

Density Of States ◽

Density Functional ◽

Theoretical Calculations ◽

Structural Parameters ◽

Lattice Parameters ◽

High Symmetry ◽

Delafossite Cualo2 ◽

Transparent Semiconductor ◽

P Type

Delafossite CuAlO2 is a p-type transparent semiconductor oxide with space group R-3m (N°166) is a material with extended applications in different fields. Structural parameters, band structure, and density of CuAlO2 have been investigated in the light of the Density Functional Theory (DFT) using PBE pseudopotentials (norm-conserving pseudopotentials). Our calculations are performed with the ABINIT package using cut-off energy of 100 Hartree, showing convergence to cut-off energy up to 30 Hartree. The lattice parameters of CuAlO2 obtained after the relaxation process are a = b = 2.904 Å and c = 17.202 Å; and consequently, volume of V=174.014 Å3 , also the derivate of the bulk modules Bo´=4.1, and bulk modulus Bo=174 Gpa were found. We find that discrepancies between our calculated lattice parameters a, c, and c/a are overestimated about 0.798%, 0.591%, and 0.219% compared to the reference’s theoretical calculations of Qi-Jun Liu et,al respectively. The calculated energy band structure of CuAlO2 and the high-symmetry points of Brillouin Zone show that the delafossite structure has an indirect band gag (~ 1.21 eV) because the top valence and the bottom conduction are found at F point and Г point, respectively. This work aims to study structural parameters, band structure, and density of states of delafossite CuAlO2 and give one application as solar cell.

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Morphology and Optical Properties of Thin Cd3As2 Films of a Dirac Semimetal Compound

Metals ◽

10.3390/met10101398 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1398

Author(s):

Natalia Kovaleva ◽

Ladislav Fekete ◽

Dagmar Chvostova ◽

Andrei Muratov

Keyword(s):

Optical Properties ◽

Band Structure ◽

Film Growth ◽

Electronic Band Structure ◽

Theoretical Calculations ◽

Wide Band ◽

Rf Magnetron Sputtering ◽

The Body ◽

Fine Tuning ◽

Electronic Band

Using atomic-force microscopy (AFM) and wide-band (0.02–8.5 eV) spectroscopic ellipsometry techniques, we investigated the morphology and optical properties of Cd3As2 films grown by non-reactive RF magnetron sputtering on two types of oriented crystalline substrates (100)p-Si and (001) α-Al2O3. The AFM study revealed the grainy morphology of the films due to island incorporation during the film growth. The complex dielectric function spectra of the annealed Cd3As2/Al2O3 films manifest pronounced interband optical transitions at 1.2 and 3.0 eV, in excellent agreement with the theoretical calculations for the body centered tetragonal Cd3As2 crystal structure. We discovered that due to electronic excitations to the Cd(s) conical bands, the low-energy absorption edge of the annealed Cd3As2 films reveals a linear dependence. We found that for the annealed Cd3As2 films, the Cd(s) conical node may be shifted in energy by about 0.08–0.18 eV above the heavy-flat As(p) valence band, determining the optical gap value. The as-grown Cd3As2 films exhibit the pronounced changes of the electronic band structure due to the doping effect associated with Cd non-stoichiometry, where fine-tuning of the Cd concentration may result in the gapless electronic band structure of Dirac semimetals.

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Effects of p-type doping and electric field on electronic band structure and optical properties of GaNAsBi/GaAs quantum well detectors operating at 1.55 μm

Thin Solid Films ◽

10.1016/j.tsf.2016.09.056 ◽

2017 ◽

Vol 630 ◽

pp. 66-70 ◽

Cited By ~ 1

Author(s):

I. Guizani ◽

C. Bilel ◽

M.M. Habchi ◽

A. Rebey ◽

B. El Jani

Keyword(s):

Optical Properties ◽

Band Structure ◽

Electric Field ◽

Quantum Well ◽

Electronic Band Structure ◽

Electronic Band ◽

P Type

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Theoretical Framework of 1,3-Thiazolium-5-Thiolates Mesoionic Compounds: Exploring the Nature of Photophysical Properties and Molecular Nonlinearity

10.26434/chemrxiv.12063261 ◽

2020 ◽

Author(s):

Zeyu Liu ◽

Shugui Hua ◽

Tian Lu ◽

Ziqi Tian

Keyword(s):

Optical Properties ◽

Rational Design ◽

Rayleigh Scattering ◽

Function Analysis ◽

Theoretical Calculations ◽

Photophysical Properties ◽

Optical Nonlinearity ◽

Nonlinear Properties ◽

Photoelectric Performance ◽

Wave Function Analysis

Inspired by a previous experimental study on the first-order hyperpolarizabilities of 1,3-thiazolium-5-thiolates mesoionic compounds using Hyper-Rayleigh scattering technique, we theoretically investigated the UV-Vis absorption spectra and every order polarizabilities of these mesoionic molecules. Based on the fact that the photophysical and nonlinear properties observed in the experiment can be perfectly replicated, our theoretical calculations explored the essential characteristics of the optical properties of the mesoionic compounds with different electron-donating groups at the level of electronic structures through various wave function analysis methods. The influence of the electron-donating ability of the donor on the optical properties of the molecules and the contribution of the mesoionic ring moiety to their optical nonlinearity are clarified, which have not been reported by any research so far. This work will help people understand the nature of optical properties of mesoionic-based molecules and provide guidance for the rational design of molecules with excellent photoelectric performance in the future.

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Ab initio calculation on the Optical Properties of AA- Stacked two dimensional Graphene, Silicene, Germanene, and Stanene

International Journal of Computational Physics Series ◽

10.29167/a1i1p46-50 ◽

2018 ◽

Vol 1 (1) ◽

pp. 46-50

Author(s):

Rita John ◽

Benita Merlin

Keyword(s):

Optical Properties ◽

Band Structure ◽

Density Functional ◽

Electronic Band Structure ◽

Complex Refractive Index ◽

Single Layer ◽

Generalized Gradient ◽

Electronic Band ◽

Wide Range ◽

Optical Region

In this study, we have analyzed the electronic band structure and optical properties of AA-stacked bilayer graphene and its 2D analogues and compared the results with single layers. The calculations have been done using Density Functional Theory with Generalized Gradient Approximation as exchange correlation potential as in CASTEP. The study on electronic band structure shows the splitting of valence and conduction bands. A band gap of 0.342eV in graphene and an infinitesimally small gap in other 2D materials are generated. Similar to a single layer, AA-stacked bilayer materials also exhibit excellent optical properties throughout the optical region from infrared to ultraviolet. Optical properties are studied along both parallel (||) and perpendicular ( ) polarization directions. The complex dielectric function (ε) and the complex refractive index (N) are calculated. The calculated values of ε and N enable us to analyze optical absorption, reflectivity, conductivity, and the electron loss function. Inferences from the study of optical properties are presented. In general the optical properties are found to be enhanced compared to its corresponding single layer. The further study brings out greater inferences towards their direct application in the optical industry through a wide range of the optical spectrum.

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The Optical Properties, Energy Band Structure, and Interfacial Conductance of a 3C-SiC(111)/Si(111) Heterostructure Grown by the Method of Atomic Substitution

Technical Physics Letters ◽

10.1134/s1063785020110243 ◽

2020 ◽

Vol 46 (11) ◽

pp. 1103-1106 ◽

Cited By ~ 1

Author(s):

S. A. Kukushkin ◽

A. V. Osipov

Keyword(s):

Optical Properties ◽

Band Structure ◽

Energy Band ◽

Energy Band Structure ◽

Atomic Substitution

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A computational study to explore the effects of copper doping concentration on phase stability, electronic band structure and optical properties of CsSrF3 fluro-perovskite

Molecular Physics ◽

10.1080/00268976.2021.1892226 ◽

2021 ◽

pp. e1892226

Author(s):

Muhammad Rizwan ◽

Waqar Azam ◽

S. S. A. Gillani ◽

I. Zeba ◽

M. Shakil ◽

...

Keyword(s):

Optical Properties ◽

Band Structure ◽

Phase Stability ◽

Doping Concentration ◽

Electronic Band Structure ◽

Computational Study ◽

Electronic Band ◽

Copper Doping

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Valence Band Mixing in GaAs/AlGaAs Quantum Wells Adjacent to Self-Assembled InAlAs Antidots

Journal of Nanomaterials ◽

10.1155/2019/5349291 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7

Author(s):

Takuya Kawazu

Keyword(s):

Optical Properties ◽

Quantum Wells ◽

Valence Band ◽

Energy Barrier ◽

Heavy Hole ◽

Electronic States ◽

Light Hole ◽

Photoluminescence Excitation ◽

Band Mixing ◽

Valence Band Mixing

Optical properties of GaAs/AlGaAs quantum wells (QWs) in the vicinity of InAlAs quantum dots (QDs) were studied and compared with a theoretical model to clarify how the QD strain affects the electronic states in the nearby QW. In0.4Al0.6As QDs are embedded at the top of the QWs; the QD layer acts as a source of strain as well as an energy barrier. Photoluminescence excitation (PLE) measurements showed that the QD formation leads to the increase in the ratio Ie-lh/Ie-hh of the PLE intensities for the light hole (lh) and the heavy hole (hh), indicating the presence of the valence band mixing. We also theoretically calculated the hh-lh mixing in the QW due to the nearby QD strain and evaluated the PLE ratio Ie-lh/Ie-hh.

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