SILICON has been making our computers work for almost half a century. All information processing is done using a million-strong horde of tiny logic gates made from element number 14. But silicon’s time may soon be up.
Moore’s law is grinding to a halt because there is a limit to how many can be squeezed on a chip.
The machine-learning boom is another problem. The Semiconductor Industry Association estimates that, on current trends, computing’s energy demands will outstrip the world’s total energy supply by 2040.
So research groups all over the world are building alternative systems that can handle large amounts of data without using silicon. All of them strive to be smaller and more power efficient than existing chips.