A research team succeeded in executing the world's fastest two-qubit gate (a fundamental arithmetic element essential for quantum computing) using a completely new method of manipulating, with an ultrafast laser, micrometer-spaced atoms cooled to absolute zero temperature. [2]

Figure 1. The world's fastest two-qubit gate between two single atoms

Figure 1 shows the past two decadequantum computingFor the past two decades, all quantum computer hardware has been pursuing faster gates to escape the effects of external noise that can degrade computational-based quantum computers are quickly attracting attention from industry, academia, and government around the world as revolutionary hardware that breaks through some limitations of superconducting and trapped-ion quantum computers, which are currently the most advanced types of quantum computers. [1]

Cold-atom based quantum computers

Cold-atom quantum computers are based on laser cooling and trapping techniques celebrated by the Nobel Prizes of 1997 (S. Chu, C. Cohen-Tannoudji and W.D. Philipps, "Cooling and trapping atoms with laser light") and 2018 (A. Ashkin, invention of the optical tweezers). These techniques facilitate the arrangement of arrays of cold atoms into arbitrary shapes with optical tweezers and allow each to be observed individually.

Because atoms are natural quantum systems, they can easily store quantum bits of information, the basic building block ("qubit") of a quantum computer (see Fig. 2). In addition, these atoms are very well-isolated from the surrounding environment and are independent of one another. [3]

Quantum gates:

Quantum gates are the basic arithmetic elements that make up quantum computing. They correspond to the logic gates such as AND and OR in conventional classical computers. There are one-qubit gates that manipulate the state of a single qubit and two-qubit gates that generate quantum entanglement between two qubits. The two-qubit gate is the source of the high-speed performance of quantum computers and is technically challenging. The one successfully implemented this time is one of the most important two-qubit gates called a “controlled-Z gate (CZ gate),” which is an operation that flips the quantum superposition of a first qubit from 0 + 1 to 0 – 1 depending on the state (0 or 1) of a second qubit. [4]

References:

1. https://headtopics.com/us/world-s-fastest-2-qubit-gate-breakthrough-for-the-realization-of-ultrafast-quantum-computers-28843439
2. https://www.trendradars.com/channels/article-1113265-worlds-fastest-2-qubit-gate-breakthrough-for-the-realization-of-ultrafast-quantum-computers/
3. https://phys.org/news/2022-08-world-fastest-two-qubit-gate-atoms.html
4. https://scitechdaily.com/worlds-fastest-2-qubit-gate-breakthrough-for-the-realization-of-ultrafast-quantum-computers/

Cite this article:

Thanusri swetha J (2022), The world's fastest two-qubit gate between two single atoms, Anatechmaz, pp.70