Data storage medium incorporating a transition metal for increased switching speed

Abstract

A data storage medium which includes a transition metal as a switching modulator is disclosed. The data storage medium is switchable by projected beam energy, has an erased signal to noise ratio that is substantially invariant with respect to written storage time, and a contrast ratio that is substantially invariant with respect to cycle history. The data storage medium is substantially oxygen free and comprises a chalcogenide and a switching modulator. The switching modulator is a transition metal, especially from the right hand column of Group VIII, e.g. nickel (Ni), palladium (Pd), and platinum (Pt). The concentration of the switching modulator in the data storage medium is high enough to suppress grain growth during written storage, to provide random crystallite orientation and to increase the erase velocity, but low enough to permit discrimination between detectable written and erased states of the data storage medium.

Dependencies are inferred from the claim text.