Femtosecond x-ray measurement of ultrafast melting and large acoustic transients.
نویسندگان
چکیده
Time-resolved x-ray diffraction with ultrashort ( approximately 300 fs), multi-keV x-ray pulses has been used to study the femtosecond laser-induced solid-to-liquid phase transition in a thin crystalline layer of germanium. Nonthermal melting is observed to take place within 300-500 fs. Following ultrafast melting we observe strong acoustic perturbations evolving on a picosecond time scale.
منابع مشابه
Direct Observation of Ultrafast Non-thermal Melting by Ultrafast X-ray Diffraction
Ultrafast nonthermal melting of femtosecond laser-irradiated germanium was observed directly for the first time using sub-picosecond, 1.54-angstrom x-ray diffraction. Such measurements allow the study of transient atomic motion fundamental to many processes in physics, chemistry, and biology.
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عنوان ژورنال:
- Physical review letters
دوره 87 22 شماره
صفحات -
تاریخ انتشار 2001