Why use a quantum computer?
This is because the semiconductors in current computers cannot be made any smaller.
The smaller they are, the more power they can generate even though they are small.
It is difficult to make them any more powerful or process them any faster.
This is sometimes referred to as the end of Moore's Law.
This is where quantum computers come in.
Along with AI and other technologies, quantum computers are talked about as a dream technology.
It is said that its processing power will exceed that of supercomputers.
What is the relationship with quantum mechanics?
Quantum computers are designed according to the rules of quantum mechanics.
Since it is a design, it is best to consider it separately from quantum mechanics.
There are two main rules. Various calculation processes can be superimposed.probabilistically. The second rule is that the measurement results can be obtained probabilistically. The superposition feature makes it possible to perform a large number of calculations and similar calculations at once, which means that the calculations can be done quickly. Also, quantum computers are able to perform calculations based on this rule by changing matter from grains to waves by cooling or otherwise reducing the size of the matter in the world, which is extremely small, to less than the size of a nanometer.
The author does not delve any deeper into quantum mechanics because he is more interested in how to use it practically than in its principles.
Hardware of Quantum Computers
To talk about hardware is to talk about the history of the development of quantum computers.
It's a rough one, but there you go.
1980s: early algorithmic research and development was underway in the absence of hardware.
↓
2000s: Gradually, the hardware was researched and developed as feasible hardware in the laboratory.
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2010s: Hardware development progressed at once.
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2020s: Manufacturers are developing commercial machines for full-scale operation.
In this way, the development of a general-purpose quantum computer that can be used for general purposes is now in full swing.
And the hardware types are
- Superconducting method (IBM's)
- Ion trap method
-
Optical quantum computer
There are many more, but these are just a few.
However, the above two and optical quantum computers have completely different calculation methods
Caution should be exercised.
Relationship between Quantum Computers and Classical Computers (Normal Computers)
Besides the fact that quantum computers work on the principles of quantum mechanics
There are differences from classical computers. The major differences are
While a classical computer consists of various components such as a CPU, memory, and input/output devices, a quantum computer consists only of a QPU and other computing devices.
Therefore, they are often used in conjunction with classical computers.
Algorithms and Software
There are quantum algorithms, like quantum gates, and the combination of these algorithms is commonly called quantum software. The algorithm is used as a subroutine in quantum software.
Simply put, the software is the parent and the algorithm is the child.
The way to utilize these is to first set the task and then pull the appropriate one for the task.
The objective has to be defined. In particular, we choose for the following assignments
- Eigenvalue calculations in quantum chemistry
- Combinatorial optimization problems
- Financial calculations
- Quantum machine learning
Use the SDK (Software Development Kit) for your software.
Qiskit and Blueqat are well-known examples.
https://qiskit.org/
https://github.com/Blueqat/Blueqat