Microsoft in hunt for the practical qubit
Looking for a technique that scales
Redmond says it has joined the search for a practical qubit, in an effort to kick along the development of quantum computers.
Head of research at Microsoft Peter Lee has told the MIT Technology Review digital summit that Redmond will be supporting research in other labs with funding, as well as doing its own work at its Station Q research lab at the University of California's Santa Barbara campus.
Of course, the finicky will pull up The Register and point out, quite accurately, that all transistors are already manifestations of quantum mechanics. So it's beholden to us to better-define the “quantum transistor”.
Actually, what Redmond is after is something that can be exploited as a “fab-friendly” qubit.
Creating qubits has become almost routine in quantum research labs – in 2012, the University of New South Wales created a single-atom qubit on silicon. However, creating qubits and getting them to behave properly, as a superposition of states rather than a quantum 1 or 0, is difficult; doing so reliably is more difficult; and creating qubits in a way that could be turned into some kind of microelectronics foundry is a long way off.
Lee knows this: he told MIT Technology Review that as far as Microsoft is aware, the current approaches to creating qubits don't scale.
Microsoft's direction is to work on a “topological qubit”, which Quanta Magazine describes here. The description “topological” refers to how entanglement is created and maintained – and the point of the work is that Redmond told MIT Review it sees the approach as more robust than other research into qubits.
Only a cynic would also note that whoever successfully builds a reliable, mass-producable qubit will have IP of incalculable value, making it unlikely that MS would follow paths where others have taken the lead. ®
Bootnote: For readers unfamiliar with quantum computing or qubits. The qubit – quantum bit – is analogous to the bits you're familiar with in classical computing. The big difference is that quantum mechanics allows a qubit to occupy a superposition of its possible states – to be 1 and 0 at the same time.
With enough qubits, a quantum computer could therefore represent an awful lot of states simultaneously. If you can then ask the quantum computer the right question, its waveform should collapse into the answer. The quantum computer therefore – in theory – lets you get a complex answer in a single operation, rather than having to step through lots of iterations, as in a classical computer. ®