Monolithically integrated terahertz quantum cascade array laser

Abstract

By integrating triple terahertz quantum cascade lasers (at ∼3.25 THz) monolithically into an array, a peak power of 213 mW is obtained at 10 K with a threshold current density of only 257 A/cm 2. The device shows distinct single-lobe far-field behaviour in the temperature range from 10 to 90 K, with a full-width at half-maximum of 36°. The highest operating temperature of the array laser is identical to that of the single ridge laser, indicating good heat dissipation design in the array. These results are promising for realising high power THz quantum cascade lasers.

A Study on the Photoelectric Properties of Dual Ridge Terahertz Quantum Cascade Lasers at 3.1 THz

“…Up to now, it is still difficult to fabricate a single-lobe phased-locked THz QCL array, except for a surface-emitting structure [ 20 ]. Nevertheless, continuous wave high-power, incoherent THz array sources are still widely desired in applications, such as illuminating and real-time imaging systems [ 21 ].…”