This Presidential Young Investigator intends to study hydrogenated amorphous silicon. This "hydrogen glass" material presents unique advantages as a system to probe the physics of disordered systems. The structural rearrangements which underlie the glassy material are readily influenced by doping and alloying, and are manifested by straight forward electronic measurements. Among the phenomena to be explored are: 1) stretched exponential relaxation; 2) the glass transition temperature; 3) flicker of 1/f noise; and 4) magnetoresistance in the hopping regime. In addition to enhancing our understanding of the basic physical properties of hydrogenated amorphous silicon these studies will enable the fabrication of amorphous semiconductor-based devices with superior qualities.
