Work on the development of quantum computers is like the search for the Holy Grail in the world of technology. Research in this area go for years, but so far more concerned with solving the fundamental problems of the nature of whether such a machine can ever exist. Large companies such as IBM, Google and Microsoft, however, are confident that this is possible. They are among the most active investors in this potential segment, often making progress despite the prevailing skepticism.

Generally speaking the benefits of quantum computers will be so many that it is difficult to describe. In short, such a machine could theoretically carry incomparably more transactions and calculations to the most powerful supercomputers in the moment. Take for example the dismantling of complex encryption key. If current machines with the high performance it will take months or even years, a quantum computer would be able to do it for a few minutes. The benefits of such computing power combined with more compact dimensions of these machines can be really impressive. But although there are many projects in this area so far none has achieved the expected theoretical possibilities of this type of device.

Inevitable “but”

Unfortunately there is always a “but”. In case the problem is that, in theory, quantum computers are a unique technological development, but in practice proved to be almost impossible. At least at this stage. Even if not everyone is convinced that something like this is possible to do. This type of devices work in an entirely different way than normal computers. In existing machines the information can be “packaged” to zeros and ones, called bits. Each bit has two states: either zero or one. A quantum computer in turn relies on the so-called quantum bits. They can be either one or zero, and both. Here is a very good example: through classic binary code a series of three bits may submit only one number from 0 to 7. That is, to record all the numbers from zero to seven, we will need eight different combinations of three bits. A series of three quantum bits, however, may present simultaneously all the numbers from zero to seven.

The advantages are that this quantum computer can calculate, process and analyze massive amounts of information and its variations for much less time. Practical one calculation can understand what are the numbers from zero to seven, instead of doing eight separate analysis. This is in theory. The practice leads to quite complex problems and challenges. Since quantum bits are completely different concept, they also need other algorithms with which to work. Furthermore quantum bits are something real, for example a photon with the polarization. May be the atom, electron, even molecule. Among the challenges is how these quantum bits to “hold” status, as any attempt to manipulate results in their decay, which, translated into computer language is tantamount to a “mistake”.

Overcoming obstacles

Solving the problem of those errors is a key element of future quantum computers. Specialists of Google and the University of California at Santa Barbara working on a possible decision. They were able to program several groups quantum bits so to detect certain errors and not allow them to compromise the outcome of the calculations. Basically, a quantum computer is constituted exactly by quantum bits groups that are linked together. In this case, the chip was programmed so that the nine quantum bits it can be “seen” one another and to monitor whether any of them will change their condition. The reason for such a change may be even the influence of neighboring quantum bits, especially in the case of photons. Rather than to correcting wrong quantum bits, the rest just “take the necessary steps to prevent a mistake of compromising subsequent steps of the operation.” What are these steps, however, still remains a secret.

Google team believes that this is a big and important step associated with the creation of quantum computers. It opens the door to work on eliminating all remaining problems. “There is more work before we say that all the elements for fault tolerant quantum calculations are in place. However, I think this project shows that we approach”, told the online edition TechnologyReview Daniel Gotesman who also seek similar methods to correct errors in quantum bits, he works for Perimeter Institute in Ontario.

Alternative have at Oxford University. His team of scientists took advantage of the concept of “magic states” of quantum bits, which was developed in 2005 by Sergei Braviy and Alexei Kitaev. These are the quantum states that are characterized by an acceptably low error rate. In order to achieve, however, it is necessary to carry out a specific process, which is called distillation, aiming to achieve a smaller number quantum bits but more stable. The problem is that it takes very serious resources from the hardware itself to achieve this goal – up to 90% of all quantum bits in a quantum computer. Scientists from Oxford have used a different method that separates quantum bits farther apart, because it is more stable and interfere less with each other. Along with a few small changes at first glance, they have achieved a significant improvement and thus require 15 times less quantum bits in “magical state”. Thus, the number of errors decreases above 20 times. The result is that it takes fewer resources for distillation.


All this sounds wonderful and it seems that quantum computers, slowly but surely, are about to become reality. But not everyone thinks so. Analyst and specialist in cryptography Ross Anderson as recently announced in its publication that the concepts of quantum computers have failed. According to him, most theories of these devices are speculative. He argued that so far none of them has been fully demonstrated.

Anderson substantiate its lack of tangible results from existing prototypes of such machines that never achieved phenomenal results, which are all expected. He believes that the industry is going in the wrong direction by trying to make a computer of “things” that still does not know well. Anderson believes that it is better to focus falls on the study of quantum mechanics, before leaving for the creation of quantum computers. Against this background, however, work on this type of machine continues. Unfortunately, it will take at least another decade before a fully operational quantum computer become reality. D.TECH NEWSTechnologyWork on the development of quantum computers is like the search for the Holy Grail in the world of technology. Research in this area go for years, but so far more concerned with solving the fundamental problems of the nature of whether such a machine can ever exist. Large...