||D. A. B. Miller, D. S. Chemla, D. J.
Eilenberger, P. W. Smith, A. C. Gossard, and W. Wiegmann, "Degenerate Four-Wave
Mixing in Room-Temperature GaAs/GaAlAs Multiple Quantum Well Structures," Appl. Phys.
Lett. 42, 925-927 (1983).
The authors report the first observation of
forward degenerate four-wave mixing (DFWM) in room-temperature GaAs/GaAlAs multiple
quantum well structures near the exciton resonances. In a sample 1.26 mu m thick with
sixty-five 96-AA GaAs quantum wells they observe approximately 10/sup -4/ diffraction
efficiency with approximately 30 W/cm/sup 2/ average intensity from a mode-locked laser.
They measure nonlinear absorption and DFWM spectra, and also a change in refractive index,
per carrier pair/cm/sup 3/, of n/sub eh/ approximately 2*10/sup -19/ cm/sup 3/ just below
the heavy hole exciton peak. With 20-ns carrier lifetime this corresponds to an effective
nonlinear coefficient for CW beams of mod n/sub 2/ mod approximately=2*10/sup -4/ cm/sup
2//W. This is appreciably larger than previous estimates and encouraging for
room-temperature all-optical devices
Full text available for