Quantum cascade laser

A quantum cascade laser (QCL) is a type of laser that produces very precise infrared light by using a series of extremely thin layers of semiconductor materials. When electricity is applied, electrons move through these layers, dropping energy at each step and emitting light in the process. Unlike traditional lasers that rely on electron transitions within atoms, QCLs generate light through a process called "interlayer electron transitions," allowing for tunable wavelengths and high power in the infrared spectrum. They are used in applications like medical imaging, environmental monitoring, and security because of their efficiency and specificity.