An Introduction on Quantum Computing

In the 1930s, the key figures like Alan Turing have developed a classical theory of computing. These theories explain the restrictions of machinable algorithms and are still used today. Most of these theories are interesting to observe that modern computers exist as you know during the 1950s. Contemporary computers were quickly developed from valve technology to VLSI integrated circuits. The modern processor design function has reached a very small stage, but they are influenced by the strange rules of quantum mechanics.

These effects indicate the size reduction limitations that were one of the important ways to improve the performance of the processor, but some new computers are these effects on quantum computers, I think it can be used for the benefits of.

Richard Feynman, in principle, LED creating an abstract model of a method that can be used to perform calculations. Next, in 1985, David Deutsch announced a revolutionary theoretical article that describes how to use the quantum computing system to fully model physical processes. He stated that a computer of this type could perform tasks such as the generation of real random numbers that classic computers can not achieve. The most powerful functionality of the quantum computer can be the ability to use the phenomenon of "quantum parallel processing" to perform certain types of calculations in part of the time made by the classic computer.

Turing Machines developed by Alan Turing. In the 1930s are theoretical devices consisting of unlimited length tapes divided into small squares. Each square can maintain the symbol (1 or 0). Or leave it blank. The Read-write device reads these symbols and blank spaces. This will show an instruction to execute a specific program on the machine. Is this a family sound? In the Turring Quantum machine, the difference is that, as well as the reading / writing head, the tape is in a quantum state. This means that the symbol on the tape is 0 or 1 or 0 and 1 superposition. In other words, both symbols are at the same time 0 and 1 (and all points between them). Standard turning machines can only be performed simultaneously, but quantum Tour machines can perform many calculations at a time.

Turning machines, today's computers work operating the bits that exist in one of the two states. To 0 or 1. Quantum computers are limited to two states. They encode information such as quantum bits or jokes that exist in the superposition. The QUBITS represent each controller that operates together to function as a computer memory and a processor and their respective control devices. Quantum computers may contain these multiple states at the same time, so it can be duplicated that today's most powerful supercomputer.

The superposition of this QUBIT provides quantum computers inherent parallelism. According to the physique David Deutsch, this parallelism allows the quantum computer to work simultaneously for millions of calculations while operating a desktop PC. 30 The QUBIT Quantum computer is equal to the processing power of conventional computers that can be performed at 10 teraflops (the step of the floating port per second). Today's typical desktop computers work at a speed measured in Gigaflops (billions of floating movement operations per second). The quantum computer of

also uses another aspect of quantum mechanics known as entanglement. A problem with quantum computer ideas is that if you try to examine the suggestive particles, you can hit them, which allows you to change its value. You will see the qubit in the superposition to determine the value. In that case, the QUBIT assumes one of 0 or 1 value, but both are not (effectively activated on a digital computer of the time series). To create a practical quantum computer, scientists should design how to indirectly measure to maintain system integrity. Quantum physics allows two atoms to apply an external force to two atoms, and the two atoms can take charge of the characteristics of the first atom. Therefore, if it is a person and it is left, it will turn slightly. At the time when interrupted, it will select a rotation or value, and at the same time, the second intertwined atoms will select the opposite turn or value. This allows scientists to know the value of Qubit without really looking at.

Next, we'll look at some recent advancements in the field of quantum computing.

QUBIT CONTROL

Computer scientists use control devices to control microscopic particles like qubits in quantum computers.

• The ion trap uses light or magnetic fields (or a combination of both) to trap ions.

• The optical trap uses light waves to trap and control particles.

• Quantum dots are made of semiconductor materials and are used to contain and manipulate electrons.

• Semiconductor impurities contain electrons by using "unwanted" atoms found in semiconductor materials.

• The superconducting circuit allows electrons to flow with little resistance at low temperatures.

The advantage of quantum computing

It is theoretically shown that the quantum computer can make classical computers that they can perform. However, this does not necessarily mean that the quantum computer has priority of classical computers for any type of function. Using a classic algorithm on a quantum computer, you can also create the classic computer. To show your superiority of the quantum computer, you must use a new algorithm to use the parallelism of the symptoms.

Such an algorithm is not easy to formulate, but once it was discovered. They bring spectacular results. An example of an algorithm of this type is a quantum factor resolution algorithm created by Peter Shor's of AT & T Bell Laboratories. The algorithm works in its main factors for significant factoring problems. This task is a classic challenge to solve. In fact, forming the basis of RSA encryption is probably very difficult to form the most common encryption method of encryption used today. The Shor's algorithm is welcoming the effect of parallel quantum processing, provides the result of the problem of the second decomposition of the factor in a few seconds. In contrast, classic computers can, in some cases, produce more than the age of the universe.

Disadvantages of quantum computing

The technology required to build quantum computers is currently out of range. This is because the basic coherent state of the operation of the quantum computer is destroyed as soon as possible by its environment. The attempt at the battle with this problem has barely not succeeded, but continues hunting for practical solutions.

The meaning of the theory involved in quantum calculus not only creates a faster team, but also scope.

Quantum Communication

Many research groups are working on quantum communication systems. They allow the sender and recipients to accept the code where it is not fulfilled directly. Principles of uncertainty, the world nature of Quantum will prevent the sender and recipients will dislocate if the chill tries to monitor the signal that is transported.

Quantum cryptography

The expected capacity of quantum calculus promises a significant improvement in the world of encryption. Ironically, the same technology also provides global encryption technology for global problems. The meaning of the Shor's factor degradation algorithm in the world of encryption is incredible. The ability to break the RSA coding system can unstable almost all current communication channels.

QUANTUM COMPUTING

In 1982, Richard Feynman, a Nobel prize-winning physicist thought up the idea of a 'quantum computer', that uses the effects of quantum physics and quantum mechanics to its advantage. The notation of a quantum computer was primarily of a theoretical interest only, but recent years developments have gain attention of the world’s popular researchers. For example, the development was the invention of an algorithm to factor large numbers on a quantum computer, by Peter Shor (Bell Laboratories). By using Shor’s algorithm, the quantum computer would be able to crack codes much more quickly than any ordinary (or classical) computer could perform. By the way a quantum computer is capable of performing Shor's algorithm that would able to break current cryptography techniques in a fraction of seconds. With the motivation provided by Shor’s algorithm, quantum computing has gathered momentum and great interest in researchers around the world are racing to be the first to create a practical quantum computer.

The word quantum derived from the Latin word quantus which means “how much”. Quantum is a discrete quantity of energy proportional in magnitude to the frequency of the radiation. An analogue discrete amount of other physical quantity, such as momentum or electric charge is known as quantum.

The only comprehensible unit by the computer is a bit (binary digit either 0 or 1) which is the smallest. So bit is the basic unit of the classical computer. One of the most intuitive representation of bit is an open(on) or closed(off) switch of the circuit. In today’s modern computer, this representation remains in transistors, with a high voltage possibly denoting a 1 and low voltage possibly denoting a 0. A two state system (0 to 1) is the building block of classical computational device.

A quantum computer is nothing like a classical computer in design; you can't for instance build one from diodes and transistors. In order to design, a new type of technology is required, a technology that enables ‘quantum bits' to exist as coherent superposition of 0 and 1 state. A quantum bit or simply qu-bit is a unit of quantum information. Qu-bit represents both the state memory and the state of entanglement in a system. Quantum entanglement is experimentally verified property of nature. It happens when the particles such as photon, electron, molecules interacts physically and then become separated. This is known as entanglement.

An example of an implementation of the qu-bit is the quantum dot which is the first step taken by the researchers for building a quantum computer. In this phenomenon a single electron is trapped inside a cage of atoms. When the dot (i.e. the electron) is exposed to a pulse of laser light of certain frequency λ for the time interval T, the electron is raised to an excited state: a second burst of laser light causes the electron to fall back to their ground state. The electron ground state and excited state can be thought of as the 0 and 1 states of the qu-bit and the application of the laser light can be regarded as a controlled NOT method as it knocks the qu-bit from 0 to 1 or from 1 to 0. It would therefore seem that quantum dots are a suitable candidate for designing a quantum computer. By the way, there are number of practical problems that are preventing this from happening:

1. The electron only remains in its excited state for about a microsecond before it falls to the ground state.

2. There is a limit to the number of computational steps.

3. Constructing quantum dots is a very difficult process because they are very small. A quantum dot measures, 10 atoms (1 nanometer) across.

The technology needed to build a computer from these dots doesn't yet exist. In the year 2011, Columbia based company D-Wave Systems demonstrated the world’s first commercially quantum computer D-Wave one operating on 128 qu-bit processor named Rainie. It performs single mathematical method named discrete optimization. By using quantum annealing, it also solves optimization problems. Some researchers found later that this system produce no speedup compared to classical computers.

It is sure that quantum computers replace silicon chip, like transistors that replaced the vacuum tubes. But for now on, the technology requisite to develop a full-fledged quantum computer is beyond the reach. In most research in quantum computing are still theoretical.