Using multiple quantum well (MQW) saturable absorbers, we passively mode locked a NaCl color center laser to produce transformhyphen;limited, pedestalhyphen;free pulses with tgr; as short as 275 fs and peak power as high as 3.7 kW. Because of exciton ionization with a 200plusmn;30 fs time constant, the MQW shows a fast absorption recovery that is comparable to our pulse widths. This fast component plays a major role in pulse shaping and may limit the pulse width. We also show that the wavelength for the short pulses can be tuned from 1.59 to 1.7 mgr;m by choosing MQWs with different band gaps.
展开▼
