Picosecond X-ray studies of coherent folded phonons in a multiple quantum well
Author
Summary, in English
Coherent folded acoustic phonons in a multilayered GaSb/InAs epitaxial heterostructure were generated by femtosecond laser pulses and studied by means of ultrafast x-ray diffraction. Coherent phonons excited simultaneously in the fundamental acoustic branch and the first back-folded branch were detected. This represents the first clear evidence for phonon branch folding based directly on the atomic motion to which x-ray diffraction is sensitive. From a comparison of the measured phonon-modulated x-ray reflectivity with simulations, evidence was found for a reduction of the laser penetration depth. This reduction can be explained by the self-modulation of the refractive index due to photogenerated free carriers.
Department/s
Publishing year
2005
Language
English
Publication/Series
Physical Review Letters
Volume
94
Full text
- Available as PDF - 426 kB
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Document type
Journal article
Publisher
American Physical Society
Topic
- Natural Sciences
- Physical Sciences
- Atom and Molecular Physics and Optics
Status
Published
ISBN/ISSN/Other
- ISSN: 1079-7114