Engineering Quantum Dots: Overcoming Challenges in Telecommunications and Human-Machine Interaction

Engineering the inhomogeneity, density, composition, and aspect ratio of self-assembled quantum dots (SAQDs) is essential for various applications, from broadband technologies to telecommunications. This paper investigates the optimization of molecular beam epitaxy (MBE) grown quantum dots in the intrinsic region of optoelectronic devices, such as lasers, highlighting the need for tailored approaches based on specific applications. For instance, superluminescent diodes used for imaging require highly inhomogeneous dots, while inhomogeneity can pose challenges for SAQD lasers in telecommunications, as non-homogeneous QDs may become parasitic and hinder lasing efficiency. This study explores quantum dot lasers by adjusting the thickness of the GaAs spacer layers, which are grown at low temperatures and situated between the dot layers. Our findings reveal enhanced performance in SAQD laser structures, achieving "no blue shift" in peak emission wavelengths—critical for human-machine interaction and photonic integrated circuit applications. Maintaining stable emission wavelengths significantly boosts the efficiency of communication systems and quantum computing platforms, facilitating rapid data processing and interaction between machines and users.