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Direct observation of two-phonon bound states in ZnTe

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 نشر من قبل Jianbo Hu
 تاريخ النشر 2010
  مجال البحث فيزياء
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A coherent two-phonon bound state has been impulsively generated in ZnTe(110) via second-order Raman scattering in the time domain for the first time. The two-phonon bound state, composed of two anticorrelated in wave vector acoustic phonons, exhibits full {Gamma}1 symmetry and has energy higher than the corresponding 2TA(X) overtone. By suppressing two-phonon fluctuations with a double-pulse excitation, the coexistence of coherently excited bound and unbound two-phonon states has been demonstrated.



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