High frequency optical phonon is generated in stimulated Raman scattering.

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The correct answer is False.

Stimulated Raman scattering is a nonlinear optical process in which a photon interacts with a material and is scattered into a different direction with a different frequency. The frequency of the scattered photon is shifted by the energy of an optical phonon, which is a quantized vibration of the crystal lattice. The energy of an optical phonon is typically much lower than the energy of a visible photon, so stimulated Raman scattering does not produce high-frequency optical phonons.

In stimulated Raman scattering, a photon with energy $\hbar\omega_1$ interacts with a material and is scattered into a different direction with energy $\hbar\omega_2$. The energy of the scattered photon is shifted by the energy of an optical phonon, $\hbar\omega_\text{ph}$, so we have

$$\hbar\omega_1 = \hbar\omega_2 + \hbar\omega_\text{ph}.$$

The energy of an optical phonon is typically much lower than the energy of a visible photon, so the frequency of the scattered photon is shifted by a very small amount. For example, in the case of silicon, the energy of an optical phonon is about 60 meV, while the energy of a visible photon is about 2 eV. This means that the frequency of the scattered photon is shifted by about 0.03%.

Stimulated Raman scattering is a very important process in many applications, such as optical communications, laser spectroscopy, and materials science. It is also used in some types of medical imaging, such as Raman spectroscopy.