Quantum computing qubit entanglement record exceeded at 51 years

New research into quantum computing has provided a record of quantum entanglement that shows we’re well on our way to post-NISQ (Noisy-Intermediate Scale Quantum) computing. The new research, led by Xiao-bo Zhu at the University of Science and Technology of China, has led to a record 51 qubits (the quantum computing equivalent of transistors) entangled, a capability needed to unlock quantum computing. probabilistic that promises to provide a quantitative leap in humanity’s processing capabilities.

Zuchongzhi, the quantum computer used to get the results of the experiments, packs 66 superconducting qubits, the same qubit technology supported by IBM and a number of other leading companies in the quantum computing space. This is the same technology that IBM recently achieved quantum utility on through its 127-qubit Eagle QPU (Quantum Processing Unit), showing various players that there is peculiar life happening in superconducting qubit space.

After cooling the superconducting qubits to the required absolute zero of outer space (273.15 degrees Celsius, 459.67 degrees Fahrenheit), the researchers then controlled and fine-tuned the states of the qubits using microwaves, which interacted with magnets of the qubits to manipulate them. in the entangled state. This was necessary for qubits to be organized into particular sequences (or logic gates), the equivalent quantum structures built with transistors to form a CPU core in standard computing, for example. This allowed scientists to perform operations that changed the states of qubits many pairs at a time, instead of a simple one-to-one connecting field. These techniques allowed the scientists to successfully entangle 51 qubits (arranged in a line) and 30 lower but still record qubits arranged in a two-dimensional plane.

Charles Hill, a researcher at the University of New South Wales in Australia, is perhaps one of the scientists best qualified to comment on the findings. Hill was involved in similar research and aimed to demonstrate similar “networked” entanglement between as many as 65 qubits.

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Entanglement is perhaps best understood in the sense that qubits become entangled in such a way that it is impossible to describe a single qubit without being able to describe all the others and how they relate to each other: it is essentially a single system, a node without any wire suspension.

In remarks given to New Scientist, Hill described entanglement as… one of the main differences between conventional computers and quantum computers, and is a key ingredient in quantum algorithms. Demonstrating a large number of entangled qubits is therefore an important landmark for a quantum computer.

At the time of its research, Hill’s team failed to demonstrate extended entanglement between qubits as a group and not just between connected pairs, the same difficulty verifying that Zhu encountered (and overcame) with the Zuchongzhi QPU.

It is relatively common that we develop new tools or new ways to observe objects or the interactions between objects. In this case, it could be that the problem Hill encountered with his 65-qubit entanglement experiment had nothing to do with the entanglement itself; only that perhaps the techniques available to verify his results were unable to provide a convincing answer. Zhu’s team had to develop a new detection protocol to test for group entanglement, something sure to be thoroughly investigated by the quantum computing community. After all, it’s not every day that the promise of trapping hundreds of qubits emerges.

Entangling clusters of qubits is one of many intermediate research opportunities that quantum scientists are pursuing, from trying to increase computational fidelity through error mitigation and perhaps correction of quantum errors, through finding intelligent ways to predict how noise will destroy your qubits and essentially negate their effects.

It is predicted that 51 entangled qubits won’t allow us to break through the quantum advantage barrier, at least not until scaling has a little more time to do its thing. But with IBM recently showing us that utility can already be mined from our current-era quantum computers, it’s not out of the realm of probability that 51 entangled qubits will unlock a given answer whose question we may not yet know.