Boolean Logic Gate Design Principles in Unconventional Computers: an NMR Case Study

There is much work on in materio computing: exploiting unconventional material substrates and their dynamical properties to perform computation, and examining their computational properties and abilities. One of the more advanced is optical computing [33, 34]. Other, more exotic, substrates include nuclear spins in NMR experiments [16, 17, 24, 6], liquid crystals [12, 13, 14], conductive media [21, 22], reaction-diffusion chemical systems [19, 23, 27, 32], DNA [3, 4], and even slime moulds [2, 31]. The aim is to allow the material to do what comes naturally, under control of physical laws, and to exploit this natural dynamics as an efficient form of