Quantification of propagating and standing surface acoustic waves by stroboscopic X-ray photoemission electron microscopy

The quantification of surface acoustic waves (SAWs) in LiNbO3 piezoelectric crystals by stroboscopic X-ray photoemission electron microscopy (XPEEM), with a temporal smearing below 80   ps and a spatial resolution below 100   nm, is reported. The contrast mechanism is the varying piezoelectric surface potential associated with the SAW phase. Thus, kinetic energy spectra of photoemitted secondary electrons measure directly the SAW electrical amplitude and allow for the quantification of the associated strain. The stroboscopic imaging combined with a deliberate detuning allows resolving and quantifying the respective standing and propagating components of SAWs from a superposition of waves. Furthermore, standing-wave components can also be imaged by low-energy electron microscopy (LEEM). Our method opens the door to studies that quantitatively correlate SAWs excitation with a variety of sample electronic, magnetic and chemical properties.

Source: Journal of Synchrotron Radiation - November 1, 2018 Category: Physics Authors: Foerster, M. Statuto, N. Casals, B. Hern á ndez-M í nguez, A. Finizio, S. Mandziak, A. Aballe, L. Hern à ndez Ferr à s, J.M. Maci à , F. Tags: surface acoustic waves (SAWs) LiNbO3 standing and propagating SAW stroboscopic XPEEM LEEM research papers Source Type: research