On World Telecommunication Day, let’s talk about why the disruptive technology quantum communication can achieve “absolute confidentiality”

Today is the 55th World Telecommunication Day.

In 1969, the 24th Administrative Council of the International Telecommunication Union passed a resolution to designate May 17 as "World Telecommunication Day".

With the continuous development of communication technology, while it has brought great convenience to people, there are also many information security risks. More and more companies and individuals are beginning to pay attention to whether the information related to themselves is safe, and whether normal communication activities will result in information loss and theft. Quantum communication is mainly to solve the problem of communication security.

According to media reports, in March this year, Academician Pan Jianwei, Professor Xu Feihu and others from the University of Science and Technology of China developed key technologies such as high-speed and high-fidelity integrated photonics quantum state control and high-counting rate superconducting single photon detection, achieving real-time quantum key distribution at a 100-megabit rate, raising the international code rate record by an order of magnitude, which is of great significance for the large-scale application of quantum communications in the future. The achievement was published on March 14 in the internationally renowned academic journal Nature Photonics.

On May 17, let’s talk about the “absolute confidentiality” of quantum communication.

What is quantum, quantum communication and quantum key

First, you need to understand some basic concepts.

Quantum is a general term for basic particles such as photons, protons, neutrons, electrons, and mesons, and is the most basic carrier of energy.

Quantum is the smallest, indivisible basic unit in the physical world and the most basic carrier of energy. It is a general term for elementary particles such as photons, protons, neutrons, electrons, and mesons. It can be said that the entire world is made up of quanta. For example, the light in our daily lives is made up of a large number of photons.

Quantum communication is an important branch of quantum information science. It uses the principles of quantum mechanics to manipulate quantum states and exchange information between two locations, completing tasks that classical communication cannot accomplish. It has two most typical applications, one is quantum key distribution and the other is quantum teleportation. Quantum key distribution overcomes the inherent security risks of classical encryption technology and is the only communication method that has been strictly proven to be unconditionally secure in principle.

Quantum key distribution is a method of transmitting and measuring the quantum state of light to generate quantum keys that cannot be intercepted or tampered with and have complete quantum randomness. The key is presented in the form of binary bits, which can establish unbreakable encryption for various data communications, namely quantum encryption communication.

Why is quantum technology highly confidential?

Quantum encryption can use the laws of physics to ensure the uniqueness of information. This technology is essential, instantaneous, and theoretically unbreakable. In quantum information, there is a very basic theorem called the "quantum no-cloning theorem", which can ensure that quantum bits cannot be accurately copied.

In previous communication methods, even if the sender sealed the envelope and stamped it with wax, it was impossible to prevent someone from opening it, reading it, and then restoring it. When using electromagnetic waves to transmit a secret, no matter how low the "volume" is, it cannot prevent careful eavesdropping. In the end, we can try to lower the "volume" to such a level that the information is extremely weak - the quantum level, and particles in the quantum state have the property of "self-destruction". Any spy who measures it will destroy it, and any careful reading will completely change it, and it is impossible to change it only a little bit. At the same time, copying will also destroy the information and let the user know. It is also this property that makes it very suitable as a "confidentiality tool."

By utilizing this feature, quantum communication is guaranteed to be secure.

Will quantum communication replace traditional communication in the future?

Expert Zhang Wenzhuo introduced: "In fact, the goal of quantum communication is not to replace traditional digital communication. For example, quantum key distribution itself is to make traditional digital communication more secure and cannot exist independently. Quantum teleportation depends entirely on the development of quantum computers. Only when all classical computers are replaced by quantum computers in the future will this communication method be fully used. But the problem is that quantum computers and traditional computers are like nuclear weapons and conventional weapons. It is impossible for them to completely replace each other. In the future, quantum communication and traditional communication should work together to build a space-ground integrated communication network."

With the deepening of quantum information research and application, perhaps in the near future, quantum communication technology will become as common as mobile phones and computers and enter the homes of ordinary people.