A quantum well is a thin layer of semiconductor material that confines charge carriers, such as electrons and holes, in a very small space. This confinement occurs in one dimension, allowing the carriers to move freely in the other two dimensions. The result is quantized energy levels, meaning the carriers can only occupy specific energy states. Quantum wells are essential in various electronic and optoelectronic devices. These structures are commonly used in laser diodes, light-emitting diodes (LEDs), and photodetectors. By manipulating the thickness and material composition of the quantum well, engineers can tailor the properties of these devices, enhancing their performance in applications like telecommunications and imaging.