Establishing a quantum internet via optical fiber: A step towards the practical use of quantum computers

Establishing a quantum internet via optical fiber: A step towards the practical use of quantum computers

2024-04-25 23:06:00

Several quantum computers have already been built. They have done some calculations and are said to have already produced some fascinating results.

Although there are critical voices that deny quantum computers practical use or at least question the time and resources needed to research them, the theory is promising.

A few hundred qubits would be enough to outperform modern processors with billions of transistors. This is due to quantum entanglements that form between qubits. These higher levels of two, three or more qubits increase performance, similar to interconnected neurons in the human brain.

However, this information based on quantum entanglements can hardly be extracted, much less stored or transmitted, which ultimately amounts to the same thing. Photons also interact with each other.

This means that two photons in a packet contain more information than two photons taken separately and added together. More than the sum of the individual parts, if you will.

This complex act of transferring and storing photons was carried out as part of a collaboration between several European universities, including two British and two German universities in London, Southampton, Stuttgart and Würzburg.

Scientists have successfully constructed transmitters and receivers of entangled quantum particles. Transfer and subsequent storage in particular have caused major problems until now. The study reflects almost five years of research.

It was necessary to develop a new system, because existing transmissions rely on the widest possible spectrum of light so that the photons do not interfere. But this is exactly what must happen with the entangled quantum network.

The solution is a “quantum dot”, a packet of unentangled photons passing through a quantum memory system. A circuit made of rubidium atoms is used to store the photons and the information they record.

As complex as this construction is, fiber optic cables, such as those used in many Internet connections, are suitable for transmitting the photons themselves. With a wavelength of just under 1,500 nanometers, outside the visible range, quantum dots are in the standard frequency band.

They will at least enable the creation of quantum networks, although their success in terms of storage is currently limited to a few moments, not to mention the overall effort involved.

1714100685
#Establishing #quantum #internet #optical #fiber #step #practical #quantum #computers

Leave a Replay