Scientists approach Is the internet By creating the world’s first multi-node quantum network
Researchers from the QuTech Research Center in the Netherlands have created a system consisting of three quantum nodes that are entangled in the formidable laws of Quantum mechanics That controls subatomic particles For the first time, more than two quantum bits, or “qubits,” computed in a quantum computer, are linked together as “nodes” or network endpoints.
The researchers expect the first quantum network to unlock a number of computing applications that could not be achieved by existing classic devices, such as faster computation and enhanced encryption.
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“It will allow us to connect quantum computers for more processing power, build un-hacked networks, and connect atomic clocks and telescopes with unprecedented levels of coordination.” It has been there before, ”Matteo Pompili, a member of the QuTech research team building networks at the Delft University of Technology in the Netherlands, told Live Science. Algorithms that will hold elections safely, etc. ”
In the same way that traditional computer bits are the basic unit of digital information, qubit is the fundamental unit of quantum information. Like the bit, the qubit can be 1 or 0, representing two possible positions in a two-state system.
But that’s just the end of the similarities. Thanks to the strange law of the quantum world, the qubit can exist in the superposition of both states 1 and 0 up to a measurable moment when it will randomly collapse to 1 or 0.This strange behavior is key. For the power of quantum computers, as it allows the qubit to perform multiple calculations simultaneously.
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The greatest challenge in linking these qubits together as quantum networks is creating and maintaining a process known as entanglement, or what Albert Einstein dubbed “the term terrifying action.” This is when two qubits combine to link their properties so that any change in one particle will cause a change in the other, even if they are separated by a large distance.
You can intervene a quantum node in a number of ways. But one common method works by binding a stationary cubit. (Which are nodes of a network) with photons or particles of light before firing them together. When they met, the two photons were entangled. This binds two stationary nodes separated by a distance. Any change made to one thing will be reflected by an immediate change to another.
The “distant terror action” allows scientists to change the state of particles by changing the state of their intertwined counterparts, effectively transmitting information through large gaps. But maintaining the state of the entanglement is a difficult task, especially when entangled systems are always vulnerable to their interactions with the outside world and are destroyed by a process known as destruction.
This means that, first of all, quantum nodes must be stored at extremely cold temperatures inside devices called cryostats to reduce the chance of qubits interfering with something outside the system. Second, the photons used in entanglement cannot travel very long distances before they are absorbed or scattered – destroying the signals transmitted between the two nodes.
“The problem is that you can’t amplify a quantum signal, unlike classic networks. If you try to copy a qubit, you will destroy the original copy,” Pompili said, referring to the “qubit.” “The Non-Cloning Theorem” in physics which states it is impossible. To create identical copies of the unknown quantum state. ”This limits the distance we can send a quantum signal to tens of hundreds of kilometers. Someone on the other side of the world, you’ll need a relay node in between. ”
To solve the problem, the team created a network with three nodes in which photons “pass” the entanglement from the qubit at one of the outer nodes to the middle node. The central node has two qubits – one to get a tangled state and one to keep. When the mess between one external node and the middle node is kept, the middle node entangles the other external node with the backup qubit.When this is done, the middle node entangles two qubits, causing the outer node qubits to tangle.
But this bizarre quantum mechanical spin design in The classic “river riddle” is at least the researchers’ problem – strange, of course, but not too complicated. To properly create tangled photons and send them to nodes, researchers need a sophisticated system of mirrors and laser lights. The very difficult part is the technological challenge of reducing annoying noise in the system as well as making sure that all the lasers used to produce photons are perfectly synchronized.
“We’re talking about having three to four lasers for every node, so you’re starting to have 10 lasers and three cryostats running at the same time with all the electronics and synchronization,” Pompili said.
Three-node systems are particularly useful because the memory qubit allows researchers to clutter across network nodes individually, rather than being more demanding to do it all at once. As soon as this is done, the data will be sent through the network.
The next step for some researchers with their new network is to try and distribute this information, along with improving critical elements of the network’s computational capabilities so that it can function like a network. General computer These will determine the size that the new quantum networks can reach.
They want to see if their system will allow for an entanglement between Delft and The Hague, two Dutch cities approximately 10 kilometers apart.
“Right now, all of our nodes are within 10 to 20 meters. [32 to 66 feet] Each other “If you want something useful, you have to go the kilometer. This will be the first time for us to link long distances. “
The researchers published their findings April 16 in the journal. science.
Originally published in Live Science.