Time-resolved observation of coherent phonons by the Franz-Keldysh effect.
نویسندگان
چکیده
We report on the time-resolved observation of coherent optical phonons in GaAs by the Franz-Keldysh effect. This effect leads to a modulation of the optical interband transitions with a nonlinear dependence on the macroscopic electric field associated with the coherent phonons. We find that the nonlinear electro-optic effect forms a far more efficient detection mechanism for coherent phonons than the linear electro-optic effect near the band gap.
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عنوان ژورنال:
- Physical review. B, Condensed matter
دوره 53 11 شماره
صفحات -
تاریخ انتشار 1996