Transcript Lattice-Vibrations – Phonons in Solid State

Lattice Vibrations –
Phonons in Solids
Alex Mathew
University of Rochester
What is a phonon?
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Phonon – Quantum of lattice vibration
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Photon – Quantum of electromagnetic
radiation
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Important Concept in Solid State Physics
Origin of phonon
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Lattice – Harmonic Oscillators
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Two solution to equations of motion
Optical mode
Associated with radiation interaction
 Acoustic mode
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Maxwell-Bolzmann
Fermi-Dirac
Bose-Einstein
Phonons
BOSONS
integer spin
Phonon and Solid State
Specific Heat
T3 dependence at low temperature
1.
2. Thermal and Electrical Conductivity
Phonons- Heat carriers in non-metals
3. Phonon and Superconductivity
Transmission of Sound
Long-wavelength phonons
 Reflectivity of Ionic Crystals
 Vibrational Spectroscopy
Raman scattering – Optical Phonons
Brillouin scattering – Acoustic Phonons
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Thank you