Numerical proceeding to calculate impurity states in 2D semiconductor heterostructures
Volodymyr Akimov1,2, Viktor Tulupenko3,4, Roman Demediuk5
1Facultad de Ciencias Básicas, Universidad de Medellín, Medellín, Colombia. intremum@gmail.com.
Scientific Reports
|December 27, 2024
Summary
This study details a numerical method for calculating electronic states in semiconductor quantum wells perturbed by impurity centers. The findings offer insights into localized and resonant states in nanostructures.
Area of Science:
- Condensed Matter Physics
- Quantum Mechanics
- Materials Science
Background:
- Semiconductor nanostructures like quantum wells exhibit unique electronic properties.
- Perturbation by impurity centers significantly alters confined electronic states.
- Understanding these altered states is crucial for designing advanced electronic devices.
Purpose of the Study:
- To present a numerical expansion method for calculating electronic states in quantum wells.
- To investigate localized and resonant electronic states due to impurity potentials.
- To classify excited resonant and non-resonant states in a GaAs/AlGaAs quantum well.
Main Methods:
- Utilized the effective mass approximation.
- Employed a numerical expansion method to solve for energy positions and wave functions.
- Calculated and classified several excited states, including resonant and non-resonant ones.
Main Results:
- Successfully calculated energy positions and wave functions for perturbed electronic states.
- Identified and classified various excited resonant and non-resonant states.
- Provided detailed numerical proceeding for the expansion method.
Conclusions:
- The expansion method is effective for analyzing electronic states in quantum well nanostructures.
- Results align with existing literature, validating the numerical approach.
- The study contributes to the understanding of impurity effects on quantum well electronic properties.
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