Terahertz quantum cascade lasers: 10 years of active region and material progresses

Ten years after its first demonstration in the Terahertz, quantum cascade laser technology has made significant strides towards becoming a relevant device for real-world applications. A better understanding of the loss mechanism due to the injection process as well as the development of new materials such as the InGaAs/InGaSb/InP hold great promises for improving the maximum operating temperature of these devices.