Information About

What it's about

This course studies the use of Lasers to create ultrasound waves inside thin films of various materials. Wave behaviour, and material properties study are included.

Lectures:

Wave Propagation in Anisotropic Solids

Lecture 1:

• Elastodynamics Plane waves in infinite media:
  • Christoffel tensor, slowness curves
  • Isotropic materials
  • Anisotropic materials
• Matlab codes: slowness.m

Lecture 2:

• Poynting vector
• Energy / Group velocity

Lecture 3:

• Rayleigh Waves:
  • Isotropic Materials
  • Anisotropic Materials
• Matlab codes: rayleigh.m

Lecture 4:

• Lamb Waves in Isotropic Plates

Optical Measurement of Ultrasound

Lecture 5:

• Electrodynamics Optical Interferometry
  • Two-beam interference
  • SNR considerations

Lecture 6:

• Reference beam interferometers
• Time-delay interferometers

Lecture 7/8:

• Fabry-Perot interferometer

Lecture 9:

• Adaptive holographic interferometers

Optical Generation of Ultrasound

Lecture 10:

• EM-absorption in isotropic media

Lecture 11:

• Temperature increase due to EM-absorbed heat sources
• Ultrasound generation via rapid thermal expansion sources

Term Projects:

Team A: Rayleigh waves on cubic crystals

• Literature search
• Theoretical calculations for SAW, pseudo-SAW and SH-waves using nominal properties on (001) and (010) surfaces
• Acousto-optical experimental measurements
• Determination of elastic stiffness constants from measured data
• Report and presentation

Team B: Lamb waves in isotropic plates and free-standing thin films

• Literature search
• Theoretical calculations for dispersion curves
• Acousto-optical experimental measurements
• Determination of elastic stiffness constants from measured data
• Report and presentation

Contact:

Instructor: Prof. Sridhar Krishnaswamy
e-mail: s-krishnaswamy@northwestern.edu

[ Course web site ]