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joelio36
- 22
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I can't figure this out/find the answer. Why are acoustic phonons very low loss (i.e. earthquake P and S waves), but optical phonons die out rapidly?
Thanks,
Joel
Thanks,
Joel
Optical phonons have a limited travel distance because they are highly localized vibrations of the crystal lattice, and their energy is easily dissipated through interactions with defects and impurities in the crystal structure.
Optical phonons have a direct impact on thermal conductivity because they contribute to the transfer of heat through the crystal lattice. However, their limited travel distance can also hinder the overall thermal conductivity of a material.
No, optical phonons can only exist in materials with a crystal lattice structure, such as metals, semiconductors, and insulators. Amorphous materials do not have a defined crystal structure and therefore cannot support optical phonons.
Defects and impurities in the crystal structure can scatter and absorb optical phonons, reducing their travel distance. This is because these imperfections disrupt the regular vibrations of the crystal lattice, making it more difficult for the phonons to propagate.
Yes, the travel distance of optical phonons can be increased by reducing the number of defects and impurities in the crystal lattice. This can be achieved through careful material preparation and processing techniques. Additionally, certain crystal structures, such as diamond, have a higher phonon travel distance compared to others.