Effect of Conduction Band Non-Parabolicity on the Nonlinear Optical Properties in GaAs/Ga1−xAlxAs Double Semi-V-shaped Quantum Wells

In this paper, we investigate the effect of conduction band non-parabolicity (NPBE) on the third harmonic generation(THG), the linear and nonlinear intersub-band optical absorption coefficients (OACs) related with electronic states of double semi-V-shaped GaAs/Ga1−xAlxAs quantum wells(QWs) by using the compact-density-matrix approach. Simultaneously, the work is performed in the position dependent effective mass in order to compute the electronic structure for the system by the finite difference and self-consistent techniques. We also compare the results with and without considering NPBE. It is found that: (1) the NPBE has a significant influence on the sub-band energy levels of double semi-V-shaped QWs, and (2) the amplitude and position of the resonant peaks of the THG and nonlinear OACs in the case of considering NPBE show complicated behavior due to the energy dependent effective mass m*(E) where the energy value was chosen self-consistently.

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Third-Harmonic Generation in Special Parabolic Quantum Wells

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.760-762.392 ◽

2013 ◽

Vol 760-762 ◽

pp. 392-396

Author(s):

You Bin Yu

Keyword(s):

Quantum Well ◽

Density Matrix ◽

Quantum Wells ◽

Harmonic Generation ◽

Third Harmonic Generation ◽

Third Harmonic ◽

The Third ◽

Compact Density ◽

Asymmetric Quantum ◽

Parabolic Quantum Wells

Third-harmonic generation in a special asymmetric quantum well is investigated. The third-harmonic generation coefficient is carried out by applying compact-density-matrix method. The numerical results are presented for a GaAs/AlGaAs asymmetric quantum well. The very large third-harmonic generation coefficient is obtained in this quantum well. Moreover, the third-harmonic generation coefficient dependents on the quantum well parameters are investigated, respectively.

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ELECTRON–PHONON INTERACTION EFFECTS ON THIRD-HARMONIC GENERATION IN CYLINDRICAL QUANTUM WIRES

International Journal of Modern Physics B ◽

10.1142/s0217979204023647 ◽

2004 ◽

Vol 18 (01) ◽

pp. 53-61 ◽

Cited By ~ 4

Author(s):

YOU-BIN YU ◽

KANG-XIAN GUO

Keyword(s):

Iterative Method ◽

Harmonic Generation ◽

Quantum Wires ◽

Third Harmonic Generation ◽

Matrix Approach ◽

Phonon Interaction ◽

Third Harmonic ◽

Electron Phonon Interaction ◽

The Third ◽

Compact Density

The influence of electron–phonon interaction on third-harmonic generation in cylindrical quantum wires are investigated. The third-harmonic generation coefficient is obtained using compact-density-matrix approach and iterative method, and the numerical results are presented for GaAs cylindrical quantum wires. The results show that the third-harmonic generation coefficient is greatly enhanced after taking into consideration the influence of electron–phonon interaction. It is about thirty times larger than that obtained by just considering electron states when electron–phonon resonance is met.

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Polaron effects on the third-harmonic generation in asymmetrical semi-exponential quantum wells

Journal of Optics ◽

10.1088/2040-8978/17/3/035505 ◽

2015 ◽

Vol 17 (3) ◽

pp. 035505 ◽

Cited By ~ 7

Author(s):

Kang-Xian Guo ◽

Bo Xiao ◽

Yingchu Zhou ◽

Zhongmin Zhang

Keyword(s):

Quantum Wells ◽

Harmonic Generation ◽

Third Harmonic Generation ◽

Third Harmonic ◽

The Third

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THIRD-HARMONIC GENERATION OF WURTZITEGaN-BASED COUPLING QUANTUM WELLS WITH STRONG BUILT-IN ELECTRIC FIELDS

Modern Physics Letters B ◽

10.1142/s0217984907014309 ◽

2007 ◽

Vol 21 (27) ◽

pp. 1837-1845 ◽

Cited By ~ 2

Author(s):

LI ZHANG

Keyword(s):

Quantum Well ◽

Density Matrix ◽

Quantum Wells ◽

Electric Fields ◽

Harmonic Generation ◽

Structural Parameters ◽

Third Harmonic Generation ◽

Matrix Approach ◽

Third Harmonic ◽

The Third

Based on the density matrix approach and iterative treatment, the third-harmonic generation (THG) susceptibility of a wurtzite nitride coupling quantum well (CQW) with strong built-in electric fields have been theoretically investigated. The band non-parabolicity effect of nitride heterostructures has been taken into account. A typical wurtzite AlGaN/GaN CQW are chosen to perform numerical calculations. The result shows that, the THG coefficients sensitively depend on the structural parameters of the CQW system. Moreover, a strong THG process can be realized in the nitride CQW by choosing a group of appropriate structural parameters and doped fraction.

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Polaron Excitations in Buckminsterfullerenes: Doped C60 and C70

International Journal of Modern Physics B ◽

10.1142/s0217979292002036 ◽

1992 ◽

Vol 06 (23n24) ◽

pp. 3935-3939

Author(s):

Kikuo Harigaya

Keyword(s):

Adiabatic Approximation ◽

Energy Levels ◽

Third Harmonic Generation ◽

Low Frequencies ◽

Third Harmonic ◽

The Third ◽

Numerical Iteration ◽

Occupied State ◽

Additional Charges ◽

Phonon Model

We propose a Su-Schrieffer-Heeger type electron-phonon model for buckminsterfullerenes: C 60 and C 70. The model is solved by a numerical iteration method with applying the adiabatic approximation to phonons. When the system ( C 60 or C 70) is doped with one or two electrons (or holes), the additional charges accumulate almost along an equatorial line of the molecule. The dimerization becomes weaker almost along the same line. Two energy levels intrude largely in the gap; one is the occupied state and the other is the empty state. The intrusion is larger in C 70 than in C 60. These are “polarons” in doped buckminsterfullerenes. It is also found that C 60 and C 70 are related mutually with respect to electronical structures as well as lattice geometries. We also calculate optical properties of C 60. In optical absorption of the doped C 60, there is a new peak at the lower energy than those of the intergap transition peaks. The third harmonic generation in low frequencies agrees with experiments. Relations of polarons with recent experiments are pointed out.

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Studies on the third-harmonic generation coefficients in asymmetrical semi-exponential quantum wells

Superlattices and Microstructures ◽

10.1016/j.spmi.2013.11.016 ◽

2014 ◽

Vol 65 ◽

pp. 309-318 ◽

Cited By ~ 10

Author(s):

Sen Mou ◽

Kangxian Guo ◽

Bo Xiao

Keyword(s):

Quantum Wells ◽

Harmonic Generation ◽

Third Harmonic Generation ◽

Third Harmonic ◽

The Third

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OPTICAL PROPERTIES OF A GaAs PYRAMID QUANTUM DOT: SECOND- AND THIRD-HARMONIC GENERATION

International Journal of Modern Physics B ◽

10.1142/s0217979214500532 ◽

2014 ◽

Vol 28 (07) ◽

pp. 1450053 ◽

Cited By ~ 7

Author(s):

H. BAHRAMIYAN ◽

R. KHORDAD

Keyword(s):

Quantum Dot ◽

Harmonic Generation ◽

Second Harmonic ◽

Structural Parameters ◽

Energy Levels ◽

Great Influence ◽

Third Harmonic Generation ◽

Vertex Angle ◽

Third Harmonic ◽

Compact Density

In the present work, we have studied the second-harmonic generation (SHG) and third-harmonic generation (THG) in a pyramid quantum dot. For this purpose, we first obtain the energy levels and wavefunctions of this system. Then, we have used an analytic expression for the SHG and THG by a compact density matrix approach and an iterative procedure. The SHG and THG enhance and shift to lower energies by increasing the height (h) and vertex angle (φ). According to the results, it is found that the structural parameters have great influence on the SHG and THG of a pyramid quantum dot.

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Ultrafast Third-Order Nonlinear Optical Response Excited by fs Laser Pulses at 1550 nm in GaN Crystals

Materials ◽

10.3390/ma14123194 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3194

Author(s):

Adrian Petris ◽

Petronela Gheorghe ◽

Tudor Braniste ◽

Ion Tiginyanu

Keyword(s):

Harmonic Generation ◽

Nonlinear Optical ◽

Laser Pulses ◽

Third Harmonic Generation ◽

High Repetition Rate ◽

Third Order ◽

Third Harmonic ◽

The Third ◽

High Repetition ◽

Gan Crystal

The ultrafast third-order optical nonlinearity of c-plane GaN crystal, excited by ultrashort (fs) high-repetition-rate laser pulses at 1550 nm, wavelength important for optical communications, is investigated for the first time by optical third-harmonic generation in non-phase-matching conditions. As the thermo-optic effect that can arise in the sample by cumulative thermal effects induced by high-repetition-rate laser pulses cannot be responsible for the third-harmonic generation, the ultrafast nonlinear optical effect of solely electronic origin is the only one involved in this process. The third-order nonlinear optical susceptibility of GaN crystal responsible for the third-harmonic generation process, an important indicative parameter for the potential use of this material in ultrafast photonic functionalities, is determined.

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