Fri20Oct20174:00 pmLewis 101
Colloquium: Picosecond Ultrasonics: Nanoscale Imaging and GHz Surface Acoustic Wave Studies
Department of Physics and Astronomy
Picosecond Ultrasonics: Nanoscale Imaging and GHz Surface Acoustic Wave Studies
Ultrafast lasers produce pulses of light that are less than 1 ps in duration, and can be used to generate and detect extremely high frequency ultrasound in the range of about 100 GHz. This technique can be applied to semiconductor metrology (nanometer scale thickness measurements, mechanical properties of thin films, imaging of sub-surface nanostructures) but also provides a window to the fundamental behavior of long-wavelength acoustic phonons that have a significant impact on thermal transport at the nanoscale. In this talk I will review the picosecond ultrasonic measurement technique and discuss recent work to advance nanoscale imaging and the study of surface acoustic waves.