PhD in Physics- Condensed Matter Physics in Bethlehem United States | Lehigh University

Our research encompasses molecular materials, organic and inorganic semiconductors, wide bandgap semiconductors, point defects, rare earth doping, and ferroelectrics. We investigate exciton behavior in molecular crystals and organic semiconductors, examining singlet exciton fission and triplet exciton fusion through pump-probe spectroscopy and fluorescence dynamics (Biaggio). Additional methodologies involve nonlinear optical spectroscopy (Biaggio), infrared optical spectroscopy under hydrostatic pressure and magnetic fields (Stavola), and studies of point defects in insulating materials with ferroelectric domain walls. We also explore rare earth excitation in wide bandgap semiconductors and single crystal formation dynamics in glass (Dierolf). Current semiconductor defect research focuses on light-element impurity complexes (H, C, O, N), analyzed through vibrational spectroscopy and uniaxial stress techniques to reveal microscopic properties (Stavola, Fowler). Further studies include Raman/neutron scattering, dielectric/ultrasonic spectroscopies, and collective vibrational dynamics in disordered ferroelectrics and glasses (Toulouse).