Hello. It is @hunhani.

Thank you for your interest and support in the previous posts. I will do my best to meet your expectations.

Last time, We have learned about what is the qubit and how does it used for quantum information processing.

Chapter 5. Technological Challenges to Overcome for Quantum Information World This time, let's talk about technical challenges we have to overcome for the world of quantum information.

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Simple Review

Qubit! Basic unit of quantum information.

• Qubit adopts the appropriate quantum mechanical system and uses a new unit of information that can have 0 and 1 at the same time.

Find the average value with only one operation!

• If you want to find out the average value through operations of tens of millions of cases using a qubit with quantum parallelism means that it is possible to find the average value in a single operation.

The quantum computer can offset the wrong answer and amplify the correct answer.

• If there is a regularity in the problem to be solved with structure enabling offset, the quantum algorithms have an exponential speed improvement over the classically known best algorithms.

The attitude that we treat quantum computers

• There is a big difference between the speed of quantum computer and that of regular computer in terms of their characteristic and application so that all of the regular computers that we use will not become useless, but quantum computers and regular computers will start to help and compete with each other in maximizing their technical efficiency.

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Hardware development is the first step for the implementation of quantum computers.

Technologies such as quantum information processing, quantum communication, quantum cryptography, and etc, solve problems that conventional computers can not solve, and ultimately lead the world to the age of quantum information. The theoretical work on this issue has been quite advanced to this day. For example, the security systems based on the prime factorization for the large number widely used in the military, financial, and administrative security fields can easily be destroyed by a quantum computer. In addition to the prime factorization for the large number, quantum algorithm for the problems such as database search and linear equation has already been developed that allows quantum computers to efficiently solve this problem. Although it is necessary to derive the quantum algorithms for a variety of problems, no matter how good the quantum algorithm is, above all things, the quantum computer can be implemented with the hardware to operate it. Experimentally, there has been a steady attempt to carry out actual quantum numerical calculations with a very small number of qubits, but there are still many technical steps to overcome.

Quantum mechanical properties and principles

• Duality of particle and wave
• Uncertainty
• Quantum superposition
• Quantum entanglement
• Quantum parallelism

Core technology elements

• Generation of quantum states
• Matintenance of quantum states
• Control of quantum states
• Transmission of quantum states
• Measurement of quantum states
• Quantum algorithm

Related Application Technology

• Quantum Processor: A device that computes, processes, and controls the information based on the technology of generation, maintenance, control, transmission, and measurement of qubits.
• Quantum Communication: A system of information transmission/reception and network management based on the technology of generation, maintenance, control, transmission, and measurement of qubits.
• Quantum Repeater: A device that extends physically limited quantum entangled remote transmission distances over long distances based on the technology of semiconductor, ion-trapping, and etc.
• *Quantum Cryptography: A system of security that guarantees the non-reproducible and absolutely-safe against eavesdropping based on the technology of quantum encryption protocol, true random number generation, quantum signal post processing, fast encryption algorithm, and etc.
• Quantum Memory and Measurement: A system of ultra-precise or ultra-sensitive storage and measurement based on the technology of quantum clock, quantum image switching and modulation, quantum phase gate, quantum optical coherence tomography, quantum lithography, and etc.

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A quantum computer is the integration of quantum processors.

First of all, it is necessary to induce strong interactions between electrons or photons in the micro world, make them entangled, maintain and control them well in order to operate properly as qubit, the basic unit of quantum information. All materials have two different properties of particles and waves. Electrons with strong particle properties are relatively easy to transfer, but the errors in computation or measurement are frequent, while photons with strong wave properties are relatively difficult to transfer, but the errors in computation and measurement are infrequent. Surely, the process of making a lot of entangled quantities and handling them is a very difficult task. From the core application technologies outlined above to the related application technologies, there is a long way to go, but the prominent IT companies and the most prestigious research institutes are raising their enthusiasm for developing quantum computers, so we expect to see meaningful results in the not too distant future

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Next time, we will deal with current status of technology development for quantum computer

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I want to deliver it as easily as possible, but this topic is very difficult for everyone. If you comment your question, I will reply to you as easily and concisely as I can.

The following chapter is introduced.

Chapter 6. Current Status of Technology Development for Quantum Computer

Please do not take your eyes off!

Previous Story

• [Quantum Computer & Blockchain Security] Chapter 0. Introduction
• [Quantum Computer & Blockchain Security] Chapter 1. Quantum computer! What the hell is different with ordinary computer?
• [Quantum Computer & Blockchain Security] Chapter 2. Magical phenomena of nature, Quantum Superposition & Entanglement.
• [Quantum Computer & Blockchain Security] Chapter 3. Janus-faced quantum computer Quantum Parallelism and Quantum Communication Security
• [Quantum Computer & Blockchain Security] Chapter 4. Quantum Information Processing using Qubits
• [Next-generation Transportation] Hyperloop! Why is it so special?
• [Review] 18 Stories to See “Interstellar” Movie More Fun with Physics
• Engineer Dream Diodes with a Graphene Interlayer

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• All images used in this post are from Google Images.

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