Description

1. Core Advantages
Reduced Threshold Current Density: A typical single quantum well consists of quantum barriers and intermediate quantum well materials. With a thickness of only a few nanometers in one dimension, it can significantly reduce the volume of the laser active region, thereby greatly lowering the threshold current density and enhancing the energy efficiency of the device.
Balanced Power Performance: The extension of the quantum well in the other two dimensions helps improve the power performance of the laser, achieving a balance between “low threshold current and high power output”.
Flexible Wavelength Design: The emission wavelength of the quantum well is determined by the electron energy level difference between the conduction band bottom and the valence band top, and is also related to the quantum well thickness. The laser emission range can be precisely adjusted by modifying the composition and thickness of the quantum well material, offering extremely high design flexibility.
2. Design Considerations
In practical design, key factors affecting the critical parameters of the laser must be focused on, including: the sub-level distribution in the strained quantum well, the variation law of material gain with carriers, and the variation trend of material gain peak with temperature. These factors directly determine the core performance indicators of the laser, such as threshold current, slope efficiency, and temperature drift.
3. Typical Example
Taking the Al₀.₃Ga₀.₇As/GaAs quantum well as an example, according to the solid-state band theory, the band gap of GaAs in the quantum well is lower than that of the Al₀.₃Ga₀.₇As barrier layer. Electrons and holes are confined to the conduction band bottom and valence band top of the quantum well, respectively, ensuring the directionality and stability of light emission.
4. Application Fields
It is suitable for scenarios requiring high precision in device performance and wavelength controllability, such as high-performance lasers (e.g., high-frequency communication lasers, precision sensing lasers), high-brightness light-emitting diodes, and quantum well-based solar cells.