@article {Winkler:660, title = {Insulator-to-metal transition in sulfur-doped silicon}, journal = {Phys. Rev. Lett.}, volume = {106}, year = {2011}, pages = {178701{\textendash}}, abstract = {We observe an insulator-to-metal (I{\textendash}M) transition in crystalline silicon doped with sulfur to non-equilibrium concentrations using ion implantation followed by pulsed laser melting and rapid resolidification. This I{\textendash}M transition is due to a dopant known to produce only deep levels at equilibrium concentrations. Temperature-dependent conductivity and Hall effect data measured for temperatures T \> 1.7 K both indicate that a transition from insulating to metallic conduction occurs at a peak sulfur concentration between 1.8 and 4.3 {\texttimes} 1020 cm{\textendash}3. Conduction in insulating samples is consistent with variable range hopping with a Coulomb gap. The capacity for deep states to effect metallic conduction by delocalization is the only known route to bulk intermediate band photovoltaics in silicon.}, url = {/files/mazur/files/rep_660.pdf}, author = {M. T. Winkler and D. Recht and M. Sher and A. J. Said and Mazur, E. and M. J. Aziz} }