1. Lattice Vibrations – Phonons in Solids Alex Mathew University of Rochester

2. What is a phonon?  Phonon – Quantum of lattice vibration  Photon – Quantum of electromagnetic radiation  Important Concept in Solid State Physics

3. Origin of phonon  Lattice – Harmonic Oscillators  Two solution to equations of motion  Optical mode Associated with radiation interaction  Acoustic mode

6. Maxwell-Bolzmann Fermi-Dirac Bose-Einstein Phonons BOSONS integer spin

7. Phonon and Solid State 1. Specific Heat T 3 dependence at low temperature 2. Thermal and Electrical Conductivity Phonons- Heat carriers in non-metals

8. 3. Phonon and Superconductivity

9.  Transmission of Sound Long-wavelength phonons  Reflectivity of Ionic Crystals  Vibrational Spectroscopy Raman scattering – Optical Phonons Brillouin scattering – Acoustic Phonons

10. Thank you