Quasi-crystal distributed feedback lasers do not require any form of mirror cavity to amplify and extract radiation. Once implemented on the top surface of a semiconductor laser, a quasi-crystal pattern can be used to tune both the radiation feedback and the extraction of highly radiative and high-quality-factor optical modes that do not have a defined symmetric or anti-symmetric nature. Therefore, this methodology offers the possibility to achieve efficient emission, combined with tailored spectra and controlled beam divergence. Here, we apply this concept to a one-dimensional quantum cascade wire laser. By lithographically patterning a series of air slits with different widths, following the Octonacci sequence, on the top metal layer of a double-metal quantum cascade laser operating at THz frequencies, we can vary the emission from single-frequency-mode to multimode over a 530-GHz bandwidth, achieving a maximum peak optical power of 240 mW (190 mW) in multimode (single-frequency-mode) lasers, with record slope efficiencies for multimode surface-emitting disordered THz lasers up to ≈570 mW/A at 78 K and ≈720 mW/A at 20 K and wall-plug efficiencies of η ≈ 1%.

准晶体分布反馈激光器不需要任何形式的镜腔即可放大和提取辐射。一旦在半导体激光器的顶面上实现，准晶体图案就可以用于调整辐射反馈以及不具有定义的对称或反对称的高辐射和高品质因数光学模式的提取性质。因此，这种方法与定制光谱和可控光束发散相结合，提供了实现高效发射的可能性。在这里，我们将此概念应用于一维量子级联线激光器。通过按照Octonacci顺序，在以THz频率工作的双金属量子级联激光器的顶部金属层上，对具有不同宽度的一系列气隙进行光刻构图，η≈1  ％。