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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Polarization effects on quantum levels in InN/GaN quantum wells
Wei Lin1, Shuping Li, Junyong Kang
1Fujian Key Lab of Semiconductor Materials and Applications, Department of Physics, Xiamen University, Xiamen 361005, People's Republic of China.
Nanotechnology
|November 6, 2009
Summary
Investigating polarization effects in Indium Nitride/Gallium Nitride (InN/GaN) quantum wells reveals that strain-induced polarization modifies band bending. This research offers insights into enhancing light emission by optimizing polarization fields.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Quantum Mechanics
Background:
- Quantum wells are crucial for optoelectronic devices.
- Polarization effects in semiconductor heterostructures can significantly influence their electronic and optical properties.
Purpose of the Study:
- To investigate the impact of polarization on quantum states in InN/GaN quantum wells.
- To understand how strain and well thickness affect polarization and band bending.
- To explore methods for improving transition probability and light emission.
Main Methods:
- Ab initio calculations were employed to model the electronic structure.
- Spectroscopic ellipsometry was used for experimental validation.
- Analysis of partial densities of states, band structures, and partial charge densities.
Main Results:
- Polarization, modified by strain and well thickness, causes asymmetric band bending in the quantum well.
- Larger polarization fields increase the overall transition probability.
- Enhanced overlap between excited quantum states (2h) and electron states (1e), along with hybridization, contributes to increased transition probability.
Conclusions:
- The study demonstrates a clear link between polarization fields and transition probability in InN/GaN quantum wells.
- Findings suggest that manipulating polarization fields offers a novel approach to enhance light emission efficiency.
- This work provides a theoretical and experimental basis for designing improved optoelectronic devices.
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