Data are written or read using larger or smaller current pulses, respectively.

Nonvolatile electronic memory devices that store data in the form of electrical-resistance values, and memory circuits based on such devices, have been invented. These devices and circuits exploit an electrically-variableresistance phenomenon that occurs in thin films of certain oxides that exhibit the colossal magnetoresistive (CMR) effect. It is worth emphasizing that, as stated in the immediately preceding article, these devices function at room temperature and do not depend on externally applied magnetic fields.