Researchers at the PSI at the Paul Scherrer Institute have come up with a detailed plan to find out how quantum bits (qubits) can be created faster and better defined. The central elements are magnetic atoms of a class of metals called rare earths, which would selectively enter the crystal lattice of a material. Each of these atoms represents a qubit. Researchers have shown how these qubits can be activated, tangled, used as memory bits, and readable. They have published in the magazine their design concept and support calculations PRX file.
In the way of quantum computers, the initial requirement is to create quantum bits or so-called “qubits”: memory bits, unlike classical bits, can take not only binary values of zero and one, but also any arbitrary combination. these situations. “With this, a completely new type of computing and data processing is possible, which means a tremendous acceleration of computing power for specific applications,” explains PSI researcher Manuel Grimm, the first author of a new article on qubit.
Manuel Grimm is a theoretical physicist at the Paul Scherrer Institute and works on the basics of building quantum computers for the future. Credit: Paul Scherrer Institute / Markus Fischer
The authors describe how logical bits can be made and the basic operations on them in a magnetic solid: qubits would be in individual atoms from the class of rare earth elements, embedded in the crystal lattice of the host material. Based on quantum physics, the authors calculated that the nuclear rotation of rare earth atoms would be suitable for use as a carrier of information, i.e., as a qubit. They also propose that laser pulses can transfer information at the moment atomthey activate electrons and therefore qubits, thus making their information visible to the surrounding atoms. Two such activated qubits communicate with each other and can thus be “entangled”. Entanglement is a unique property of quantum particles or multi-qubit systems that is essential for quantum computers: the result of measuring one qubit directly depends on the measurement results of other qubits and vice versa.
The faster it has fewer errors
Researchers have demonstrated how these qubits can be used to create logical gates, especially a “controlled NOT gate” (CNOT gate). Logic gates are also the basic constructions that classical computers use to make calculations. If the CNOT gate and the single qubit gate are sufficiently combined, every conceivable computational operation is possible. They thus form the basis of quantum computers.
This article does not propose quantum-based logic gates. “Our method of activating and entangling qubits, however, has a crucial advantage over previous comparable proposals: it’s at least ten times faster,” says Grimm. The advantage, however, is not only the speed that a quantum computer based on this concept can calculate; above all, it deals with the sensitivity of the system to error. “Qubits is not very stable. If the entanglement process is too slow, there is a higher probability that some qubits will lose information in a few qubits, “Grimme explained.
Reference: Manuel Grimm, Adrian Beckert, Gabriel Aeppli, and Markus Müller, “January 21, 2021,” “A Universal Quantum Computer Using the Functions of Electronic Waves in Rare Earths.” Like PRX.
DOI: 10.1103 / PRXQuantum.2.010312