Titel: Nano-Quakes on a Chip: Surface acoustic waves in semiconductor physics
Surface acoustic waves on a piezoelectric substrate are accompanied by
strong lateral and vertical electric fields that propagate at the speed
of sound across the substrates surface. On a semiconductor layered
system, these electric fields can be used probe the dynamics of free
carriers as confined in a quantum well or to deliberately alter the
bandstructure of the employed heterostructure. A combination of both
effects can result in devices for high frequency and optical signal
In my talk, I will briefly review our activity investigating the
interaction between surface acoustic waves and semiconductor layered
- - In the quantum Hall effect, SAW can be used to probe the dynamic
conductivity of quasi two-dimensional electron systems at low
temperatures and in high magnetic fields.
- - Acoustoelectric effects prove the momentum transfer between the wave
and an electronic system.
- - The optical properties of a semiconductor quantum well can be
significantly altered under the influence of a SAW.
- - Charge storage in the lateral potential wells of a SAW and sound
induced delay of photonic signals is demonstrated.
- - Hybridization of a thin semiconductor film and a strongly
piezoelectric insulator can be used to create a very intense sound wave
leading to the dynamic creation of charged wires and to the occurence of
strongly nonlinear interactions.
- - Finally, the same hybridization technique led us to the realization of
room temperature operating high frequency devices for remote sensing