Sacnning near-field and confocal microscopies provide unique methods of characterizing a wide variety of semiconductor, dielectric, and hybrid optoelectronic materials and interfaces. We are developing methods of nanoscopic multiphoton spectroscopy and nonlinear optics for examining local structural and electronic properties of the wide-bandgap III-nitride alloy semiconductors with particular emphasis on quantum-confined heterostructures formed in compound III-nitride nanowires. The techniques include ultraviolet (UV) second-harmonic generation in addition to cw and time-resolved, multiphoton UV spectroscopy that employ NSOM and confocal techniques. We are particularly interested in the study of local defects, polytyping, inversion domains, and alloy segregation. We are also interested in studies of nanoscale strain and piezoelectricity, and the impact of such phenomena on the spectroscopy of quantum confined wires and discs. Our efforts are generally collaborative with other NIST staff that specialize in high-resolution cathodoluminescence, TEM, EBSD, and CBED.

 

key words

Confocal microscopy; Gallium nitride; Multiphoton spectroscopy; Nanowires; Near-field microscopy (NSOM); Near-field spectroscopy; Solid immersion lens microscopy; Three-nitride semiconductors; Ultrafast nonlinear optics;

Citizenship:  Open to U.S. citizens

Level:  Open to Postdoctoral applicants