连续波工作的耦合双光栅太赫兹量子级联线激光器OA

We demonstrate terahertz quantum cascade(THz-QC)wire lasers based on dual coupled gratings that achieve continuous-wave(CW)operation near liquid nitrogen temperatures with a low-divergence Gaussian-like beam profile.Our configuration circumvents the effective refractive index constraint,significantly enhancing fab-rication efficiency while retaining the key advantages of low power consumption and high heat dissipation efficien-cy.By engineering the photonic band structure of the coupled gratings,the laser operates on two supermodes.For Supermode#1,grating 1 serves as the master oscillator while grating 2 functions as a phased antenna array,featuring a collimated beam.For Supermode#2,grating 2 is the main oscillator and simultaneously provides a collimated beam,while grating 1 offers high reflectivity.Both supermodes exhibit high cavity quality factors and low beam divergence,achieved with a significantly reduced gain area.Experimentally,both supermodes are ob-served,and the optimized laser produces a collimated Gaussian beam with divergence angles of 12°×18° and an optical power of 1.04 mW.The threshold power consumption and thermal resistance are as low as 2.62 W and 8.5 mK/W/cm²,respectively,resulting in a maximum CW operating temperature of 78.0 K.This work offers a more accessible route for low-divergence,low-power-consumption,high-thermal-dissipation-efficiency THz-QCLs with enhanced CW operation at elevated temperatures.