Optimized second-harmonic generation in quantum cascade lasers Academic Article uri icon


  • Optimized second-harmonic generation (SHG) in quantum cascade (QC) lasers with specially designed active regions is reported. Nonlinear optical cascades of resonantly coupled intersubband transitions with giant second-order nonlinearities were integrated with each QC-laser active region. QC lasers with three-coupled quantum-well (QW) active regions showed up to 2 W of SHG light at 3.75 m wavelength at a fundamental peak power and wavelength of 1 W and 7.5 m, respectively. These lasers resulted in an external linear-to-nonlinear conversion efficiency of up to 1 W/W2. An improved 2-QW active region design at fundamental and SHG wavelengths of 9.1 and 4.55 m, respectively, resulted in a 100-fold improved external linear-to-nonlinear power conversion efficiency, i.e. up to 100 W/W 2. Full theoretical treatment of nonlinear light generation in QC lasers is given, and excellent agreement with the experimental results is obtained. For the best structure, a second-order nonlinear susceptibility of 4. 7 10-5 esu (2 104 pm/V) is calculated, about two orders of magnitude above conventional nonlinear optical materials and bulk III-V semiconductors.

published proceedings

  • IEEE Journal of Quantum Electronics

altmetric score

  • 3

author list (cited authors)

  • Gmachl, C., Belyanin, A., Sivco, D. L., Peabody, M. L., Owschimikow, N., Sergent, A. M., Capasso, F., & Cho, A. Y.

citation count

  • 84

complete list of authors

  • Gmachl, C||Belyanin, A||Sivco, DL||Peabody, ML||Owschimikow, N||Sergent, AM||Capasso, F||Cho, AY

publication date

  • November 2003