Femtosecond superradiance in multiple-section InGaN/GaN quantum well   laser structures
  We analyze theoretically a possibility of the superradiant emission (SR) in GaN-based quantum well (QW) laser heterostructures. Our model is based on travelling wave Maxwell-Bloch equations predicts building up of macroscopic coherences in the ensemble of carriers in the QWs. We show that SR is covered by the Ginzburg-Landau equation for phase transition to coherent matter state. The generation of superradiant pulses as short as 500 fs at peak powers of over 200 W has been predicted for InGaN/GaN heterostructure QWs with the peak emission in the blue/violet wavelength range. 
D. L. Boiko, P. P. Vasil'ev
cond-mat.str-el cond-mat.supr-con physics.optics