In 1947, the first transistor, the basic building block for a digital computer, was made using a semiconducting material thought to be ideal for the task: germanium. The idea of using silicon didn’t come up until midway through the next decade, and it wasn’t until 1960 that a thin layer of oxidised silicon, found in today’s most widely used transistors, was added. Quantum computing, the big hope for solving problems out of reach of today’s computers, is still struggling to reach its own silicon moment. Some of the biggest tech companies have started ramping up their attempts to build a working machine, convinced that the field has finally passed the threshold between interesting science experiment and practical engineering challenge. Yet there is no consensus about the best way to make the most basic elements of quantum computers, known as qubits — or indeed, whether future machines will be based on an array of different technologies rather than just one, with different types of machine suited to different computing problems. This lack of agreement on something so basic is a sobering reminder of how far quantum computing still has to go to prove itself. It also suggests that the race taking shape between some of the biggest tech companies is likely to produce winners and losers, as some qubits fail to pan out.

Full opinion : Despite breakthroughs from Amazon and Microsoft, the industry is still a long way from building practical machines.