Abstract
The intensity-dependent intersubband absorption in GaAs/AlGaAs quantum wells with a subband separation smaller than the optical phonon energy has been measured with a pulsed far-infrared free-electron laser. Complete bleaching of the absorption is observed at I=200 kW/cm2. Fitting the data with a two-level system yields a characteristic time constant of 1-2 ps. Possible interpretations, considering the finite pulse width of the laser, are discussed.
| Original language | English |
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| Pages (from-to) | 3315-3317 |
| Number of pages | 3 |
| Journal | Applied Physics Letters |
| Volume | 63 |
| Issue number | 24 |
| DOIs | |
| Publication status | Published - 1993 |