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Researchers from the Austrian Academy of Sciences and the University of Vienna have experimentally demonstrated what was previously only a theoretical possibility. Together with quantum physicists from the University of Science and Technology of China, they have succeeded in teleporting complex high-dimensional quantum states. The research teams report this international first in the journal “Physical Review Letters”.

In their study, the researchers teleported the quantum state of one photon (light particle) to another distant one. Previously, only two-level states (“qubits”) had been transmitted, i.e., information with values “0” or “1”. However, the scientists succeeded in teleporting a three-level state, a so-called “qutrit”. In quantum physics, unlike in classical computer science, “0” and “1” are not an ‘either/or’ – both simultaneously, or anything in between, is also possible. The Austrian-Chinese team has now demonstrated this in practice with a third possibility “2”.

Novel experimental method.

A team of physicists claims to have discovered a new state of matter — a breakthrough that could vastly improve traditional as well as quantum computing.

The new state, called “topological superconductivity,” could help to increase storage capabilities in electronic devices and enhance quantum computing.

RELATED: ‘QUTRIT’ EXPERIMENTS SHOW PROGRESS IN QUANTUM TELEPORTATION

By Leah Crane

Some ideas about the quantum world appear to suggest there are many versions of you spread out across many parallel universes. Now, two scientists have formulated a proof that attempts to show this is really true.

The proof involves a fundamental construct in quantum mechanics called Bell’s theorem. This theorem deals with situations where particles interact with each other, become entangled, and then go their separate ways. It is what’s called a “no-go theorem”, one designed to show that some assumption about how the world works is not true.

For the first time, Chinese scientists have demonstrated the experiment of transferring quantum information in a 3D state.

Limited in a two-level state for a long time, the study paves the way to teleporting the complete quantum state of a particle, according to an article in American Physical Society a top peer-review journal.

According to Pan Jianwei, coauthor of the study known as the “father of quantum” in China, quantum teleportation is a new communication method to transfer quantum information – a particle’s quantum state in the micro-world.

Down the road

The end game for quantum computing is a fully functional, universal fault-tolerant gate computer. To fulfill its promise, it needs thousands, maybe even millions, of qubits that can run arbitrary quantum algorithms and solve extremely complex problems and simulations.

Before we can build a quantum machine like that, we have a lot of development work to be done. In general terms, we need:

The potential for quantum computing to crack other countries’ encrypted networks has captured the attention of national governments. Which of the world’s fundamental challenges could be solved by quantum computing?

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In a world-first, researchers have created a quantum chip that contains four entangled particles of light, known as photons, and is capable of performing actions over hundreds of channels simultaneously.

Or to put that into context, they’ve come closer than ever before to building a chip that’s similar to the ones in our smartphones and computers, but that has the potential to perform exponentially more calculations, and can process data at the speed of light. Sounds good, right?

“This represents an unprecedented level of sophistication in generating entangled photons on a chip,” said co-lead researcher David Moss, from Swinburne University of Technology in Australia.

A potentially useful material for building quantum computers has been unearthed at the National Institute of Standards and Technology (NIST), whose scientists have found a superconductor that could sidestep one of the primary obstacles standing in the way of effective quantum logic circuits.

Newly discovered properties in the compound uranium ditelluride, or UTe2, show that it could prove highly resistant to one of the nemeses of quantum computer development — the difficulty with making such a computer’s memory storage switches, called qubits, function long enough to finish a computation before losing the delicate physical relationship that allows them to operate as a group. This relationship, called quantum coherence, is hard to maintain because of disturbances from the surrounding world.

The compound’s unusual and strong resistance to magnetic fields makes it a rare bird among superconducting (SC) materials, which offer distinct advantages for qubit design, chiefly their resistance to the errors that can easily creep into quantum computation. UTe2’s exceptional behaviors could make it attractive to the nascent quantum computer industry, according to the research team’s Nick Butch.

In a classic physics experiment, scientists set up quantum entanglement between sunlight and light generated here on Earth.

The researchers in China, the United States, Germany, and the United Kingdom wondered whether any two particles of light, called photons, could show the spooky interactions governed by the rules of quantum mechanics, even if they originated from vastly distant sources. The experiment was mainly curiosity-driven, but it demonstrates that in the future, researchers might be able to use the Sun as a source of light for quantum mechanics-related purposes.

Dead or alive, left-spinning or right-spinning — in the quantum world particles such as the famous analogy of Schrödinger’s cat can be all these things at the same time. An international team, together with experts from Forschungszentrum Jülich, have now succeeded in transforming 20 entangled quantum bits into such a state of superposition. The generation of such atomic Schrödinger cat states is regarded as an important step in the development of quantum computers.