Experimental and theoretical study of the carrier capture time

We present an experimental and theoretical study of the carrier capture time into a semiconductor quantum well. We observe for the first time the predicted oscillations of the phonon emission induced capture time experimentally and found good agreement with theory. Calculations show that not only does the LO phonon emission induced capture time (ph capture) oscillate as a function of well width, but also the carrier-carrier scattering induced capture time (c-c capture) oscillates by more than an order of magnitude as a function of the active layer design. Recently, it has been shown that the carrier capture time is directly related to the modulation bandwidth in a quantum well laser. As a result, it might be possible to tailor the modulation bandwidth by optimizing the capture efficiency using a proper design of the active layer in a quantum well laser.