Memory materials: a unifying description

There are so many materials properties leading to memory that a unifying description seems impossible. However, it is easy to show that the majority of two-terminal electronic devices based on memory materials and systems, when subject to time-dependent perturbations, behave simply as, or as a combination of, memristors, memcapacitors, and meminductors; namely non-linear circuit elements with memory. This unifying description opens up new venues for digital and analog applications ranging from information storage to biologically-inspired circuits. In this review, interesting research opportunities that emerge from this new perspective will be outlined.