Experimental condensed matter physics
Research Categories: Ultrafast Semiconductor Spectroscopy Laboratory
Research Description: Dr. Everitt is the chief scientist at the U.S. Army Research Office where he also manages the Army's extramural program in quantum information science and, until very recently, the program in condensed matter physics. His program is one of the nation's largest in the areas of nanoscience and quantum computing. His pioneering support of the nascent fields of photonic band engineering and quantum information science has placed the Army in a leadership position in these rapidly growing areas. Dr. Everitt leads an active research group in condensed matter physics, nanophotonics, and astronomy in the Duke Univ. Physics Dept. and Fitzpatrick Photonics Center. The largest effort is in the ultrafast optical characterization of wide bandgap semiconductor heterostructures and nanostructures using independently tunable pump and probe wavelengths that span the ultraviolet-visible-infrared regions from 200 nm to 12 microns with pulses shorter than 150 fs. The objective is to map out and control carrier, exciton, and phonon transport and relaxation pathways in III-N semiconductors, both undoped and doped with rare-earth and magnetic atoms, using cw and time- resolved photoluminescence and differential transmission measurements. Areas of recent interest include characterization of carrier relaxation in III-N and ZnO epilayers, quantum wells, and nanostructures, modification of recombination rates through nanometer-scale engineering of plasmonic resonances, and characterization and modeling of radiative and nonradiative recombination in rare earth-doped GaN. Other areas of recent research activity have included measurement of refractive index dispersion relations in uniaxial and biaxial semiconductor thin films and the optical properties of quantum dot infrared photodetectors. Finally, Dr. Everitt performs astronomical research through collaborations on and off campus. In collaboration with the Three College Observatory of UNC-Greensboro, advanced image processing techniques have been applied to observations of galactic globular clusters in order to discover RR Lyrae variable stars ascertain their periods. In collaboration with the Prof. David Brady of the Fitzpatrick Photonics Center, rotational shear interferometers were constructed, characterized, and mounted on astronomical telescopes as a lensless technique for observing bright stars with the dual goal of atmospheric turbulence compensation and one-step, scanless spectroscopy. Finally, Dr. Everitt has investigated molecular collision dynamics in order to understand nonequilibrium atmospheres and interstellar media. In collaboration with Prof. Frank De Lucia of Ohio State Univ., Dr. Everitt was the first to map out the complete rotational and vibrational energy transfer map of methyl fluoride, leading to the demonstration of a compact, tunable, coherent source of far infrared radiation for use in ground-based spectroscopy and astronomical observation. Dr. Everitt subsequently investigated photonic crystal-based microwave and millimeter wave cavities to improve the performance of this gas-phase, far infrared laser in collaboration with Prof. Stephanos Venakides of the Duke Math Dept.
Areas of Interest:
Wide bandgap semiconductor