CHALLENGES IN APPLICATION OF A MONTE CARLO METHOD TO STUDY AN EXCITON CONFINED IN AlGaAs/GaAs SINGLE QUANTUM WELL

In this work, we have studied some computational aspects of a Monte Carlo method applied to an exciton which is confined in an AlGaAs/GaAs single quantum well. The computational pseudo-code and effect of its computational parameters like number of the Monte Carlo sampling points on a physical quantity like exciton binding energy are investigated. Then the CPU time under the change of such computational parameters are calculated. Finally, the exciton binding energy and errors of different methods of approximating the effective two dimensional coulomb potential for these systems are compared.

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Exciton binding energy and electron effective-mass in strain compensated InGaAsN/GaAs single Quantum Well

2006 IEEE LEOS Annual Meeting Conference Proceedings ◽

10.1109/leos.2006.278835 ◽

2006 ◽

Cited By ~ 1

Author(s):

Lifang Xu ◽

D. Patel ◽

C.S. Menoni ◽

Jeng-ya Yeh ◽

J. T. Huang ◽

...

Keyword(s):

Binding Energy ◽

Quantum Well ◽

Effective Mass ◽

Exciton Binding Energy ◽

Single Quantum ◽

Electron Effective Mass ◽

Single Quantum Well

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Doping effects on carrier capture in a single quantum well by ensemble Monte Carlo

Canadian Journal of Physics ◽

10.1139/p96-863 ◽

1996 ◽

Vol 74 (S1) ◽

pp. 220-224

Author(s):

B. Reid ◽

M. Abou-Khalil ◽

R. Maciejko

Keyword(s):

Monte Carlo ◽

Quantum Well ◽

Pulse Excitation ◽

Single Quantum ◽

Single Quantum Well ◽

Carrier Capture ◽

Ensemble Monte Carlo ◽

Doping Effects ◽

Long Time ◽

Femtosecond Light Pulse

Using a bipolar ensemble Monte Carlo coupled with a Poisson equation solver, we simulate, for the first time, carrier capture with both types of carriers in an InGaAs/InP-doped single quantum well, following femtosecond light-pulse excitation. We show that Coulomb interaction between electrons and holes is very efficient in keeping the capture ambipolar for a long time. However, for short times, the capture is unipolar. Our results indicate that for these kinds of experiments, Monte Carlo simulations with only one type of carrier give questionable results.

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LOCALIZED WANNIER EXCITON IN DEFECT LAYER EMBEDDED BETWEEN TWO SEMI-INFINITE SUPERLATTICES

International Journal of Modern Physics B ◽

10.1142/s0217979210052520 ◽

2010 ◽

Vol 24 (18) ◽

pp. 3501-3511

Author(s):

MENG-DONG HE ◽

LING-LING WANG ◽

WEI-QING HUANG ◽

BING-SOU ZOU ◽

KE-QIU CHEN

Keyword(s):

Binding Energy ◽

Variational Approach ◽

Exciton State ◽

Defect Layer ◽

Growth Direction ◽

Exciton Binding Energy ◽

Two Dimensional ◽

Single Quantum ◽

Single Quantum Well ◽

Peak Value

The characteristics of the localized Wannier exciton in defect layer (GaAs) embedded between two semi-infinite superlattices (GaAs/Al x Ga 1-x As ) are investigated theoretically using a variational approach. It can be clearly seen the exciton changes in character between three- and quasi-two-dimensional states from the variation of exciton binding energy, in-plane radius, and probability in the superlattices (SLs) growth direction. We find that the extensions of exciton in directions both parallel and perpendicular to the interface of SLs almost approach their minimums as the exciton binding energy reaches peak value at a certain defect width. Our results show that the binding energy of the ground exciton state is sensitive to Al concentration x in Al x Ga 1-x As and thicknesses of the constituent layers. The comparison between excitonic behavior in structural defect SLs and single quantum well is made.

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