Nanotechnology is the science that studies and models matter on the scale of one billionth of a meter (nano-meter). It represents the future in many human sectors: from electronic technology, with increasingly miniaturised circuits, to new types of medicine in which nano-objects can be used to selectively attack tumours from the inside. Additionally, the possibility of integrating our technological nano-objects with nature itself, releasing them into polluted areas and allowing them to act as filters in order to purify the environment. It is indisputably quite easy to imagine a possible negative use of such potential, starting with a new way of conceiving weapons of war both against mankind and our living environment.
But in this article, we do not want to investigate the broad spectrum of all nanotechnology’s possibilities and how it will shape our future. We’d rather like to respond to Feynman, bringing some scenic and paradigmatic examples of our current nano-technological capabilities, as he would.
And first of all, given the love that La Livella Magazine has for reading, we are going to talk about the smallest book ever “printed” (also certified by Guinness World Records), entitled “Teeny Ted from Turnip Town“, written by M. D. Chaplin and published by R. Chaplin with the collaboration of the laboratory of Simon Fraser University in Vancouver. It is a tiny silicon slab measuring 70 micrometres x 100 micrometres and is written on thirty “pages”, in which the letters are sculpted by bombarding the slab with a beam of ions (electrically charged atoms). The book is a fairy tale about Tenny Ted and his victory at a turnip competition, but you need a scanning electron microscope to read it.
The second example, also documented by Guinness World Records, is the smallest film ever produced. It is called “A Boy and His Atom” and was made by IBM scientists and posted on YouTube [1]. The film shows a stylised boy, made up of a few molecules, playing with another molecule representing his ball. Between each frame, the atoms are moved individually in a controlled manner by the scientists, who atomically ‘draw’ the various scenes. A total of sixty-five carbon monoxide molecules were used, placed on a copper underlayer as a background. The whole system was kept at a temperature close to absolute zero because at higher temperatures the atoms would have had enough energy to move even when the scientists would have not wanted them to.
The last application we mention is currently a hot topic in science and more generally in society too: the quantum computer. Since Feynman’s famous speech, when a computer would take up an entire room, progress in computing has evolved simultaneously in two directions: in the increase in computer power and in the miniaturisation of its circuits. There is a law, known as Moore’s law, which describes this trend. It predicts a doubling of the number of transistors printed on a circuit every 18 to 24 months. In simple terms, this means that the size of our technological devices is getting increasingly smaller, so that today we can use a single smartphone where once we would have had to use a multitude of devices. Moore’s law, however, has a practical, physical limit to where we must stop when reducing the size of systems. Under this limit the laws of quantum mechanics emerge, making the behaviour of matter indescribable in classical terms. Nanotechnology has brought us up to this threshold and will help us to cross it, letting us switch from the classical “bits” of 0 or 1 to the “qubits” that can be found in superposition states between 0 and 1, extending the limits of computation to which we are accustomed. From bit to qubit, the rules of cryptography, pharmaceutical industry and scientific research could take a whole new turn. Suffice it to say that in 2019 Google’s quantum processor, Sycamore, managed to solve in three minutes and twenty seconds a problem that would take the world’s most powerful non-quantum computer ten thousand years to solve. But this is another story and is worth being told in a future article.