Taking a quantum leap

This new form of computing aims to produce vastly more powerful devices able to solve bigger problems

There was for many years a legendary mathematical phenomenon known as the

RSA Factoring Challenge, created in 1991 by security company RSA Laboratories “to encourage research into computational number theory and the practical difficulty of factoring large integers”.

With prizes of up to $200,000 for finding what are known as prime factors in very large numbers, it attracted a lot of interest in the mathematical and cybersecurity worlds before being discontinued in 2007.

“If you tried to do that on a classical computer, like the best supercomputer in the world today, it would take you one billion years to go through and figure out what the prime factors are,” says Todd Holmdahl, corporate vice-president at Microsoft for quantum computing.

“Now in the quantum world, if you have a quantum computer of relative-to-moderate size, you can find those prime factors in 100 seconds.”

Quantum, the next generation of computing, is in its infancy but has the potential to fundamentally alter the world as we know it.

As Holmdahl suggests, the power of this new form of computing is phenomenal. “I have seen a lot of technologies, and I think this is the one that is really going to [affect] our generation the most,” he told the FM in Seattle.

Holmdahl says the way we’ve stored information for the past 4,000-5,000 years hasn’t changed much. In 2,500 BC, we used an abacus with beads; in the 21st century, semiconductors can store a 0 or a 1 – but still just one digit.

“The beauty of the quantum space is that you can store both a 0 and a 1 at the same time. And that, coupled with this idea of entanglement, allows you to have exponential numbers in computational spaces at your disposal.”

Simply put, a quantum computer is vastly more powerful than anything that has come before. But building one is very difficult.

A quantum computer doesn’t actually exist yet and the first one is still thought to be about 10 years away.

Microsoft’s effort to build one includes a 2mhigh dilution refrigerator filled with helium 3 and helium 4. “At the bottom of this tank is the coldest spot in the universe,” says Holmdahl. “It gets down to 15 millikelvin, right above absolute zero,” or -273°C. “This is where our qubits sit.”

A qubit (or quantum bit) is the basic unit of quantum information. It is the equivalent of current computing’s measurement scale that begins with a bit, either a 1 or a 0.

The key difference is that while the bit is a piece of information that is either a 1 or a 0, a qubit can be either or both — the latter is known as quantum superposition. If that were not complex enough, there is “entanglement”, which refers to the ability of a qubit to represent multiple pieces of data at the same time. Holmdahl says: “In the classical [computer] world, if you want to solve this [prime factor] maze you might try a path and get blocked, try another path and get blocked, and you keep going until you get through the number of searches.

“In the quantum world, what is so beautiful about it is that you effectively get to try all paths at the same time. “So it is much easier to find the answer.”

But qubits operate best at very cold temperatures, hence the elaborate cooling systems.

One plate in Microsoft’s refrigerator is set at -270°C, “the same temperature as deep space”, says Holmdahl. “Here we develop all the hardware that controls these qubits. It is very important that we don’t generate heat because heat is the enemy of a qubit.”

He says Microsoft has already created a new technology that uses the same power as the typical metal-oxide semiconductor (or CMOS) in a laptop but is 100 times more powerful.

For Microsoft, one attraction of quantum is that it could be integrated into the company’s Azure cloud computing system and offered as a service. Microsoft’s cloud computing rivals are also deeply invested in quantum research — notably IBM, Intel and Google.

But quantum computing has a significant downside to which there is not yet any real answer — its power could render encryption useless.

The internet requires data encryption for everything from online banking to social networking. Without it, nothing could be kept safe.

But a future quantum computer could hack any current encrypted data — which illustrates both the terrifying power of quantum computing as well as its intriguing potential to revolutionise society.