Research Interests

In our lab we study dynamic processes occurring in semiconductor and polymer nanostructures. For these
 studies we have developed i) high-resolution near-field characterization techniques (t-NSOM,  SANM, and  
WGAS), and  ii) a self-assembly method for fabricating  polymer nanostructures with responsive 
characteristics (PEN).

Semiconductor Materials Characterization

The “Lifetime Near-field Scanning Optical Microscope" (t-NSOM) uses a purely optical pump-probe approach for mapping semiconductors’ surfaces according to their carrier-lifetime (the average time that excited carriers take to return to equilibrium). Here, the values of t (which are affected by the presence of defects) reflect materials quality. The near-field optical approach allows better lateral spatial resolution than conventional techniques.

Characterization of mesoscopic fluid films

More recently Dr. La Rosa has incorporated ultrasonic sensing into the NSOM microscope, which enhances the versatile characteristics of the new microscope to also characterize elastic materials properties. The resulting "Shear-force/Acoustic Near-field Microscope" (SANN-M) is being used for a) Inves tigating the quite different (from the bulk) dynamic displayed by fluid-like films when subjected to mesoscopic confinement and while in intimate contact with two sliding solid boundaries; this studies have implications in nanotribology (friction studies at the nanometer scale); as well as b) for imaging subsurface material properties.