scholarly journals g-factors and discrete energy level velocities in nanoparticles

2006 ◽  
Vol 74 (12) ◽  
Author(s):  
Eduardo R. Mucciolo ◽  
Caio H. Lewenkopf ◽  
Leonid I. Glazman
Keyword(s):  
Energy Level ◽  
Discrete Energy ◽  
Discrete Energy Level ◽  
G Factors

scholarly journals Electron Population Dynamics in Optically Pumped Asymmetric Coupled Ge/SiGe Quantum Wells: Experiment and Models

Photonics ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 2 ◽  
Author(s):  
Chiara Ciano ◽  
Michele Virgilio ◽  
Luigi Bagolini ◽  
Leonetta Baldassarre ◽  
Andrea Rossetti ◽  
...  
Keyword(s):  
Energy Level ◽  
Quantum Wells ◽  
Quantum Cascade Lasers ◽  
Balance Model ◽  
Optically Pumped ◽  
Discrete Energy ◽  
Discrete Energy Level ◽  
Saturation Intensity ◽  
Sige Quantum Wells ◽  
Scattering Rates

n-type doped Ge quantum wells with SiGe barriers represent a promising heterostructure system for the development of radiation emitters in the terahertz range such as electrically pumped quantum cascade lasers and optically pumped quantum fountain lasers. The nonpolar lattice of Ge and SiGe provides electron–phonon scattering rates that are one order of magnitude lower than polar GaAs. We have developed a self-consistent numerical energy-balance model based on a rate equation approach which includes inelastic and elastic inter- and intra-subband scattering events and takes into account a realistic two-dimensional electron gas distribution in all the subband states of the Ge/SiGe quantum wells by considering subband-dependent electronic temperatures and chemical potentials. This full-subband model is compared here to the standard discrete-energy-level model, in which the material parameters are limited to few input values (scattering rates and radiative cross sections). To provide an experimental case study, we have epitaxially grown samples consisting of two asymmetric coupled quantum wells forming a three-level system, which we optically pump with a free electron laser. The benchmark quantity selected for model testing purposes is the saturation intensity at the 1→3 intersubband transition. The numerical quantum model prediction is in reasonable agreement with the experiments and therefore outperforms the discrete-energy-level analytical model, of which the prediction of the saturation intensity is off by a factor 3.

Carrier Hopping and Relaxation in InAs/GaAs Quantum Dot Heterostructures

2014 ◽  
Vol 875-877 ◽  
pp. 9-13
Author(s):  
Ya Fen Wu ◽  
Jiunn Chyi Lee
Keyword(s):  
Energy Level ◽  
Quantum Dot ◽  
Temperature Dependence ◽  
Thermal Emission ◽  
Carrier Dynamics ◽  
Photoluminescence Spectra ◽  
Discrete Energy ◽  
Discrete Energy Level ◽  
Size Uniformity ◽  
Gaas Quantum Dot

We investigate the effect of carrier dynamics on the temperature dependence of photoluminescence spectra from InAs/GaAs quantum dot heterostructures with different dot size uniformity. Intersublevel relaxation lifetimes and carrier transferring mechanisms are simulated using a model based on carriers relaxing and thermal emission of each discrete energy level in the quantum dot system. Calculated relaxation lifetimes are decreasing with temperature and have larger values for sample with lower dot size uniformity. In the quantitative discussion of carrier dynamics, the influence of thermal redistribution on carriers relaxing process of quantum dot system is demonstrated by our model.

Redshift and discrete energy level separation of self-assembled quantum dots induced by strain-reducing layer

2011 ◽  
Vol 109 (6) ◽  
pp. 064320 ◽  
Author(s):  
Yongxian Gu ◽  
Tao Yang ◽  
Haiming Ji ◽  
Pengfei Xu ◽  
Zhanguo Wang
Keyword(s):  
Quantum Dots ◽  
Energy Level ◽  
Discrete Energy ◽  
Discrete Energy Level ◽  
Self Assembled

Discrete energy level separation and the threshold temperature dependence of quantum dot lasers

2000 ◽  
Vol 77 (4) ◽  
pp. 466-468 ◽  
Author(s):  
Oleg B. Shchekin ◽  
Gyoungwon Park ◽  
Diana L. Huffaker ◽  
Dennis G. Deppe
Keyword(s):  
Energy Level ◽  
Quantum Dot ◽  
Temperature Dependence ◽  
Threshold Temperature ◽  
Quantum Dot Lasers ◽  
Discrete Energy ◽  
Discrete Energy Level

PHOTOCURRENT ABSORPTION SPECTROSCOPIC STUDY OF Si0.6Ge0.4/Si QUANTUM WELLS

2006 ◽  
Vol 20 (02) ◽  
pp. 133-140
Author(s):  
SHIHUA HUANG ◽  
FENGMIN WU ◽  
JI LIN ◽  
FANG LU
Keyword(s):  
Energy Level ◽  
Spectroscopic Study ◽  
Quantum Wells ◽  
Valence Band ◽  
Ground State ◽  
State Energy ◽  
Energy Levels ◽  
Absorption Coefficients ◽  
Discrete Energy ◽  
Discrete Energy Level

Absorption spectra of Si 0.6 Ge 0.4/ Si quantum wells are characterized by photocurrent measurements. The absorption coefficients of two different transitions, namely the transition between the Si band states and the discrete energy level in quantum wells, and the interlevel transition in quantum wells are deduced. They are directly proportional to (ℏω-ΔE)3/2 and δ(ℏω-Eeh), respectively. The valence band offsets of Si 0.6 Ge 0.4/ Si interface are 297 meV. The ground state energy levels in valence band and conduction band Si 0.6 Ge 0.4/ Si quantum wells are 37 meV and 23 meV, respectively.

Discrete energy level spectrum dependence of fractal conductance fluctuations in semiconductor billiards

2002 ◽  
Vol 13 (2-4) ◽  
pp. 683-686 ◽  
Author(s):  
A.P Micolich ◽  
R.P Taylor ◽  
R Newbury ◽  
J.P Bird ◽  
T.M Fromhold ◽  
...  
Keyword(s):  
Energy Level ◽  
Discrete Energy ◽  
Discrete Energy Level ◽  
Level Spectrum ◽  
Conductance Fluctuations

Linear and nonlinear Fano resonance in the main chain-structure of additional defects with an isolated ring composed of defects

2018 ◽  
Vol 32 (07) ◽  
pp. 1850089
Author(s):  
Xiu-Huan Ding ◽  
Rui Wang ◽  
Qian Qiao ◽  
Cun-Xi Zhang
Keyword(s):  
Energy Level ◽  
Fano Resonance ◽  
Main Chain ◽  
Chain Structure ◽  
Defect States ◽  
Discrete Energy ◽  
Discrete Energy Level ◽  
Transmission Properties ◽  
Continuum Energy ◽  
Linear And Nonlinear

As is well known, Fano resonance originates from the interference between a continuum energy band and an embedded discrete energy level. We study transmission properties of the discrete chain-structure of additional defects with an isolated ring composed of N defect states, and obtain the analytical transmission coefficient of similar Fano formula. Using the formula, we reveal conditions for perfect reflections and transmissions due to either destructive or constructive interferences. It is found that a nonlinear Kerr-like response leads to bistable transmission, and for either linear cases or nonlinear ones, the defects in main arrays have a major impact on perfect reflections, but has no effect on perfect transmission.

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