Quantum Network

Quantum network is a kind of follow the rules of quantum mechanics high-speed math and logic operations, storage and processing of quantum information physical device. When a device processing and calculating of the quantum information is, the operation is quantum algorithm, it is quantum network. The concept of quantum network computer research is originated from the reversible. Research reversible computer to solve the energy problem of computer.

The principle of quantum network

Will a particle quantum information is sent to distant another entanglement particles, the particles in receive these information, will become the original particle copies. A particle can transfer limited information, while millions of particles together, they form quantum network.

Quantum network theory basis

Quantum theory researchers have long found open quantum communication keys -- quantum entanglement. Quantum entanglement describes a phenomenon: two microscopic particles on both sides of the space in the universe, no matter how far, as long as the two particle each other quantum entanglement, it is by changing a particle of quantum state, can make very distant another particle state also change, signal transcends the barriers of time, directly to another particle there.

This amazing phenomenon and our life had said "psi" very similar, two distant people complicity to want to do the same thing, like a root invisible strings holding two men.

This theoretical over communication arouses quantum scientists ambition, they tried to establish the Internet faster than now thousands of times quantum network.

Quantum Internet history

In the 1960s and the 1970s, people found the energy consumption can lead to computer chip fever, greatly influenced chip integration, limiting the computer running speed. Research found that the calculating process of energy comes from the irreversible operation. Then, whether calculation process must use irreversible operation to complete? The answer to the question is: all the classic computer can find a corresponding reversible computer, and do not affect operation ability. Since computers every step of the operation can transform for reversible operation, then in quantum mechanics, it can use a unitary transformation to said. Early quantum network with quantum mechanics, in fact, is the classic computer language description, and did not use the essential characteristic of quantum mechanics, such as quantum state of superposition sex and coherence. In classic computer, basic information unit for bits, operation object is all sorts of bits sequence. Similarly, in quantum network, basic information unit is quantum bits, operand is quantum sequence. What is different, quantum bit sequence can not only are in various states of superposition state of orthogonal, and still can entanglement state. These special quantum state, and provides not only quantum parallel computation of may, and will also bring many wonderful properties. And classic computer network can do different, quantum arbitrary unitary transformation, get in the output state after calculating results of measurement. Therefore, quantum computing to classic greatly expanded calculation in mathematics can be formally, classic calculation is seen as a kind of special quantum computation. Quantum network for each superposition component, all these transform to transform and finish at the same time, according to a certain probability amplitude supercomposing, the result is given, the calculation called quantum parallel computing. In addition to parallel computing outside, quantum network another important use of quantum system is simulated, and the job is not competent for classic computers.

Whether quantum parallel computing or quantum calculations, essentially make use of the quantum coherence. Unfortunately, in actual system quantum coherence is difficult to maintain. In quantum network, quantum not a single system, it can interact with the external environment, led to quantum coherence attenuation, and that elimination coherent. Therefore, to make quantum computing to become a reality, a core problem is overcome away coherent. But quantum coding is ever found overcome the most effective way to extinction coherent. A few of the main quantum coding scheme is: quantum ecc, quantum avoid wrong words.if it and quantum prevent wrong words.if it. Quantum ecc is classic ecc analogy, is currently the most kind of coding research, its advantages in application scope, defect is inefficient.

Quantum network's problems

Quantum particle is fragile, a little happens will let it lose information. For example, if we look at the quantum state particles (of course, they are too small, our eyes resolution could not reach the level of tell it, but we send photon could eyes get there), its state may have been destroyed. So, for a long time, quantum network is used only as science fiction to view.

So far, there is no real sense of quantum network. However, many of the laboratory is the world with great enthusiasm tracing this dream. How to realize quantum computing, scheme and many, the problem is in the experiment of microscopic realization of quantum states manipulate really too difficult. At present already proposed scheme mainly USES the atom and light cavity interaction, cryotrapping bound ions, electrons or nuclear spin resonance, quantum dots manipulation, superconducting quantum interference, etc. It is hard to say which kind of plan more promising, but quantum dots scheme and superconducting Josephson junction scheme is more suitable for integration and miniaturization. The future may existing solutions are sent out no use, finally the is a kind of brand-new design, and the new design is based on some new materials, like semiconductor materials as for electronic computer. The purpose of the study of quantum network is not to use it to replace the existing computers. The concept of quantum computing networks make it look brand-new, this is quantum network and other computers as light computer and biological differences between computer etc. Quantum network effect was more than solve some classic computer can't solve the problem.