Just like traditional computers, quantum computers can make errors. In traditional machines, errors occur when a bit of binary data (coded as either a 1 or 0) flips which digit it should represent. If left unresolved, this type of error can result in corrupted data that is devastating for users at any level. To solve this issue in traditional machines, an extra bit is added to the end of a data string indicating whether all of its bits are correct.
As I mentioned earlier, quantum computers aren’t immune to errors; in fact, the errors that quantum computers can face are far more challenging to correct.
Due to the nature of quantum computers, a quantum bit (a qubit) doesn’t only hold the position of 1 or 0, it actually exists within a “phase” between the two binary poles and can change between positive and negative. While this type of complexity might one day allow quantum computers to process some pretty heavy calculations in an instant, it also makes error detection and correction significantly more difficult.
Or it least it did.
Critical to this new error checking mechanism was a brand new configuration for qubit architecture. In the past, quantum computers have been built in a linear fashion with qubits all in a row. IBM’s new model sees qubits stacked in a square array, allowing two methods of error correction to occur simultaneously. In addition, researchers have also developed a system that uses two qubits to check data for every two qubits on a chip. With this one-to-one ratio of “working” to “checking” qubits, IBM’s team has been able to detect quantum errors caused by quantum computing’s two nemeses, heat and radiation.
With these new error correction capabilities, IBM researchers believe they can now expand the number of qubits on their chips and finally hit the 13-17 qubit threshold. What’s so exciting about squishing 13-17 qubits on a chip? According to some people in the field, 13-17 qubits represents the point at which logic can begin to be coded into these quantum machines and the spark of computational life can be ignited.
When will we reach that point?
I’ve no idea.
However, the benefits could be enormous. According to Arvind Krishna, senior vice president and director of IBM Research, “Quantum computing could be potentially transformative, enabling us to solve problems that are impossible or impractical to solve today. While quantum computers have traditionally been explored for cryptography, one area we find very compelling is the potential for practical quantum systems to solve problems in physics and quantum chemistry that are unsolvable today. This could have enormous potential in materials or drug design, opening up a new realm of applications.”
Needless to say, the future is looking bright for quantum computers.
Source: IBM