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تسجيل مستخدم جديدDirect observation of two-phonon bound states in ZnTe
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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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