Terahertz Quantum Cascade Laser at 3.39THz

We demonstrate the growth of terahertz quantum cascade laser (THz QCL) by gas source molecular beam epitaxy. X-ray diffraction and cross-sectional transmission electron microscopic measurements show the high crystalline quality of the THz QCL active region. From the cross-sectional transmission electron microscopy image, sharp interfaces are observed and the deduced
cascade period thickness is consistent with the result of x-raydiffraction. The test device is lasing at 3.39THz and operating up to 100K in pulsed mode. At 10K, the maximum output power is greater than 1mW with a threshold current density of 738A/cm².