1.5 μm dual-lateral-mode distributed Bragg reflector laser for terahertz excitation

摘要

A terahertz excitation source based on a dual-lateral-mode distributed Bragg reflector(DBR) laser working in the 1.5 μm range is experimentally demonstrated. By optimizing the width of the ridge waveguide, the fundamental and the first-order lateral modes are obtained from the laser. The mode spacing between the two modes is9.68 nm, corresponding to a beat signal of 1.21 THz. By tuning the bias currents of the phase and DBR sections,the wavelengths of the two modes can be tuned by 2 nm, with a small strength difference( 45 dB).