Phase-change computing

Abstract

Phase-change materials and devices are currently generating much interest for their potential to provide practicable alternatives to traditional von-Neumann computing (i.e. alternatives to computing in which memory and processing functions are carried out at physically separated locations). Indeed, many years after Ovshinsky and colleagues first showed the remarkable computing capabilities of phase-change devices (see for example [1-3]), other researchers have recently experimentally demonstrated the potential of phase-change devices to perform not only arithmetic computing [4], but also to provide hardware mimics of both synapses [5, 6] and neurons [4] (so opening the way to so-called bio-inspired or neuromorphic computing). We ourselves recently demonstrated reliable execution of the four basic arithmetic operations of addition, subtraction, multiplication and division using phase-change materials and micrometrescale optical excitation with (groups of) femtosecond pulses [4]. In this paper however we demonstrate that this arithmetic capability is also accessible via the electrical domain and on the nanoscale. [...]