Academics have been working on ways to make this approach more efficient. In a paper published today in Nature, researchers at Delft University of Technology in the Netherlands and the University of Wisconsin–Madison say they were able to program a two-qubit machine based on spin qubits to execute a couple of algorithms that are typically employed to test the effectiveness of quantum machines, including one that could be used for searching a database.

Thomas Watson, one of the researchers, says the team’s advance was based on things such as finding better ways to calibrate the “gates” in the machine, or the basic quantum circuits. He thinks that silicon-based systems could ultimately allow qubits to be packed more densely together than other approaches. The closer qubits are to one another, the easier it is to get them to influence neighbors, which boosts machines’ computational power.

It isn’t just coziness that matters, though. If qubits can influence more distant neighbors as well as those near to them, then a computer will have even more computational muscle to flex. That’s been the focus of researchers at Princeton University, the University of Konstanz in Germany, and the Joint Quantum Institute/NIST in Maryland. In another paper published in Nature, they describe a method for using microwave photons to help couple distant qubits.

There’s still plenty of work to be done to get silicon-based qubits to a point where they are taken more seriously, but the potential is there. They stay in quantum states longer than their superconducting counterparts, which makes it possible to perform more operations on them. They can also function at higher temperatures, which means they don’t need such complex gear to support them.

Intel thinks all this will make it easier to scale quantum computers to the millions of qubits needed to make a really useful commercial system, which is why it has been supporting researchers working on silicon-based quantum technology. It also plans to start producing wafers with many thousands of small qubit arrays in the same factory that handles its advanced transistor technologies.

But even silicon’s biggest fan is hedging its bets in the quantum race: Intel is developing superconducting qubits too.