For more than seven years (starting in 2009), Google has been collaborating with D-Wave Systems, a Canadian tech startup which at the time claimed to be the first company to produce a commercial quantum computer. In 2013, Google even bought D-Wave Two, one of D-Wave’s machines.
Sadly, a number of tests published in 2014 debunked D-Wave’s claims — their machines were not doing any better than traditional computers because they did not seem to be using quantum physics to solve problems and run computations. Or simply, their machines weren’t quantum computers at all.
It was in that same year when University of California professor John Martinis joined Google to establish a quantum hardware lab in Santa Barbara. His mission was to develop his own versions of the kind of chip being used inside a D-Wave machine. In other words, he was tasked to make improvements on D-Wave’s hardware based on the premise that their chip had the kind of quantum physics needed to do quantum computing, it just wasn’t working the right way to deliver the superior computational power that a quantum computer is supposedly capable of.
Three years later, Martinis has given himself a clear deadline: he says that by the end of 2017, his team will be the first to achieve ‘quantum supremacy’, meaning, they will be able to build the first true quantum computer. And his confidence stems from the fact that they are now ready to test the quantum chip they have been working on for the past few years.
As reported by the MIT Technology Review, Google’s quantum chip has 6 qubits arranged in a 2 by 3 configuration which, according to Martinis, shows that the technology will work when the qubits are arranged side by side as they will need to be in bigger devices.
The use of qubits (short for quantum bits) is what makes the high speed computational power of quantum computers possible. Conventional computers process data through bits which can represent 0 or 1. Quantum computers, on the other hand, process data by using qubits that can represent 0, or 1, or 0 and 1 simultaneously through the bizarre quantum process known as superpositioning or the ability of being in two different states at once.
Aside from showing its feasibility for large scale application, Google’s 6-qubit arrangement is also a test to show if initially using one chip to store the qubits and another chip for the wiring that controls the qubits before eventually ‘bump bonding’ them together will work. Apparently, the results are positive. Which is why the team is now moving fast forward.
According to Martinis, their quantum supremacy experiment would require a 49-qubit grid. And they are now in the process of designing 30 – 50 qubit devices for this purpose.
Pulling off this experiment of making a 50-qubit device actually perform quantum computations is a giant leap that will push Google to the forefront of the race to build the first quantum computer. Make no mistake about it, if successful, this will be a giant step forward. That said however, the finish line is still quite far off and there’s much more work that needs to be done.
Still, a step forward is always a welcome development. And everyone at Google (and probably even the rest of the scientific community) is excited about the prospect of witnessing the realization of a technology that has so far been elusive and one which could fundamentally alter the way our society operates.