Current-driven insulator-conductor transition and nonvolatile memory in chromium-doped SrTiO₃ single crystals

Materials showing reversible resistive switching are attractive for today's semiconductor technology with its wide interest in nonvolatile random-access memories. In doped SrTiO₃ single crystals, we found a dc-current-induced reversible insulator-conductor transition with resistance changes of up to five orders of magnitude. This conducting state allows extremely reproducible switching between different impedance states by current pulses with a performance required for nonvolatile memories. The results indicate a type of charge-induced bulk electronic change as a prerequisite for the memory effect, scaling down to nanometer-range electrode sizes in thin films.