A few years ago, the development of ultrathin material graphene, a one-molecule thick sheet of carbon, generated a lot of buzz – but then the buzz got very quiet. Graphene may be ultrathin and ultrastrong, but its electronic applications so far seem to be limited to frequency-multipliers in radio communication. More than an endpoint, graphene has proved to be an inspiration for the development of other 2D materials. Imagine the kind of supercomputers you could build with screens so thin you could see through them, ultrabooks integrated in your clothing, smartphones that can multi-task with the speed of light...
Molybdenum disulfide and bismuth-antimony are the latest contenders to make applications like these possible.
Bismuth-antimony is already commonly used in its 3D version as a cheap thermoelectric material, used in devices that convert temperature differences into electricity. Like graphene, it forms so-called Dirac cones in its 2D state. In these cones, electrons behave like massless photons, which means that they can travel much faster than in for example silicon chips, resulting in much greater computational power. Furthermore, each film of bismuth-antimony can be manipulated to have other properties, so layers of the same material with different characteristics can be used to build a whole device, instead of having to use different materials.
Molybdenum disulfide (MoS2), on the other hand, was already used two-dimensionally as an industrial lubricant, but has recently been introduced as a platform for electronic components. The main advantage MoS2 has over graphene is its natural bandgap, the property required to create transistors, which act as switches or amplifiers for electronic signals, so the material can be used for digital applications. Without a bandgap, graphene can only form switches that can be turned on, but not turned off again. Because MoS2 is already produced on a large scale, just for different applications, its implementation would be relatively cheap and easy.
So, realistically, what would a computer made of bismuth-antimony and molybdenum disulfide be like?
Its screen could fill the entire wall of your office – or even the windows, since it would be transparent anyway – while using only a fraction of the amount of raw materials required for existing monitors. Its electronics would be mobile, but instead of carrying a device in the pocket of your coat, all circuits would be embedded in your coat itself. Yes, processing power would almost reach the speed of light. And all of this using a fraction of the energy consumed by your current devices. Development is still in the early stages, of course, but the future looks bright, strong, fast, and very thin – like an incredibly futuristic ultrabook.