@mastersthesis {Kim:124,
	title = {Ultrafast Carrier and Lattice Dynamics in Highly Photo-Excited Solids},
	year = {2001},
	pages = {199},
	school = {Harvard University},
	type = {phd},
	abstract = {In this dissertation we report femtosecond time-resolved measurements of the spectra dielectric function of amourphous GaAs,GeSb thin films and single-crystalline Te. In all materials we measured the evolution of the dielectric function over a broad energy range (1.7 3.4 eV), following an impulsive excitation by an ultrashort laser pulse. The dielectric function data on a-GaAs show evidence of a nonthermal, structurally driven semiconductor-to-metal transition. A comparison to previously taken dielectric function data on c-GaAs is especially illuminating in terms of the influence of the initial structure on the phase transition. Our results on GeSb thin films reveal a new nonthermal, metallic phase.The dielectric function data provide a detailed picture of the transition from the amorphous phase to the crystalline phase of these thin films.Furthermore we refute a previous claim on an ultrafast disorder-to-order transformation in these materials. The time-resolved dielectric function data on Te reveal a great wealth of new information on impulsively driven coherent phonons, including their in fluence on the electronic bandstructure. We find evidence indicative of a new nonthermal phase of matter which we call a frustrated metal .},
	author = {A. M.-T. Kim}
}
