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Updated: Jun 19, 2026

Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
Effects of two-photon absorption on degenerate four-wave mixing in solutions of diphenyl polyenes
Abstract:
We have observed double-peaked phase-conjugate pulses in the degenerate four-wave mixing of nanosecond laser pulses in solutions of diphenyl polyenes. We attribute this to the superposition of fast and slow gratings, where the slow grating is due to two-photon absorption. This is supported by the results of time delay and polarization experiments as well as evidence of a second spatial harmonic grating.
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