Nanoscale depth-resolved coherent femtosecond motion in laser-excited bismuth.
نویسندگان
چکیده
We employ grazing-incidence femtosecond x-ray diffraction to characterize the coherent, femtosecond laser-induced lattice motion of a bismuth crystal as a function of depth from the surface with a temporal resolution of 193+/-8 fs. The data show direct consequences on the lattice motion from carrier diffusion and electron-hole interaction, allowing us to estimate an effective diffusion rate of D=2.3+/-0.3 cm(2)/s for the highly excited carriers and an electron-hole interaction time of 260+/-20 fs.
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عنوان ژورنال:
- Physical review letters
دوره 100 15 شماره
صفحات -
تاریخ انتشار 2008