Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: quantum physics – Page 73

Enhanced quantum computers and beyond: Exploring magnons with superconducting qubits

Devices taking advantage of the collective quantum behavior of spin excitations in magnetic materials—known as magnons—have the potential to improve quantum computing devices. However, using magnons in quantum devices requires an in-depth understanding of their nature and limitations. A new experimental technique uses superconducting qubits to sensitively characterize magnon behavior in previously unexplored regimes.

Researchers in the Grainger College of Engineering at the University of Illinois Urbana-Champaign have reported in the journal Physical Review Applied that highly excited magnon behavior in can be accurately characterized by coupling the material to a superconducting qubit via a microwave cavity. This setup allowed the researchers to characterize both the number of magnons and their lifetimes when thousands of excitations are present, a regime that has not been studied well.

“To be useful in quantum computing applications, limitations on magnon systems need to be understood properly,” said Sonia Rani, the study’s lead author. “The problem is that there isn’t a good theory for when certain effects become important, and if we should expect them to lead to detrimental effects.

Q&A: Companies are racing to develop the first useful quantum computer—ultracold neutral atoms could be the key

The race to build the first useful quantum computer is on and may revolutionize the world with brand new capabilities, from medicine to freight logistics.

Tech companies all want to take the crown, with Microsoft announcing the first of its kind quantum chip in February, only days before Google’s breakthrough on .

As the race heats up, companies are turning to a new ultracold solution—neutral atoms—which Swinburne University of Technology has been exploring and making discoveries in for two decades.

3D Time Could Solve Physics’ Biggest Problem, Says Bizarre New Study

Clocks might be far more fundamental to physics than we ever realized.

A new theory suggests what we see around us – from the smallest of quantum actions to the cosmic crawl of entire galaxies – could all be literally a matter of time. Three dimensions of time, in fact.

The basic idea of 3D time isn’t new. But University of Alaska geophysicist Gunther Kletetschka says his mathematical framework is the first to reproduce known properties of the Universe, making it a somewhat serious contender for uniting physics under one consistent model.

Discovery in quantum materials could make electronics 1,000 times faster

Researchers at Northeastern University have discovered how to change the electronic state of matter on demand, a breakthrough that could make electronics 1,000 times faster and more efficient.

By switching from insulating to conducting and vice versa, the discovery creates the potential to replace silicon components in electronics with exponentially smaller and faster quantum materials.

“Processors work in gigahertz right now,” said Alberto de la Torre, assistant professor of physics and lead author of the research. “The speed of change that this would enable would allow you to go to terahertz.”

Quantum Entanglement: The “Spooky” Glue Uniting Qubits and Beyond

From enabling quantum supercomputers to securing communications and teleporting quantum states, entanglement is the thread weaving through all of quantum technology. What once struck Einstein as a paradox is today routinely observed and harnessed in labs – the “spooky action” has become a practical tool. We have learned that entanglement is not some esoteric fringe effect; it’s a concrete physical resource, much like energy or information, that can be exploited to do tasks that are otherwise impossible. Its special correlations allow quantum computers to perform massively parallel computations in a single wavefunction, allow cryptographers to detect eavesdroppers with absolute certainty, and allow quantum states to be transmitted without moving a physical carrier.

Yet, there is still much to master. Entangling a handful of qubits is easy; doing so with thousands or millions – while keeping them error-corrected – remains a grand challenge. As we push the number of entangled particles higher, we are essentially scaling up new forms of matter (entangled states) that have no counterpart in classical physics. In 2022, a 12-qubit entangled state might be a small quantum circuit; by 2035, we could be operating machines where 1,000 qubits are all entangled in complex ways, delivering computational feats far beyond today’s reach. On the communications front, nascent quantum networks are entangling nodes over city-scale distances, working toward a future quantum internet that could interconnect quantum computers or enable clock synchronization and sensing with unprecedented precision. Each improvement in generating high-quality entanglement over distance inches us closer to unhackable global communication links.

Entanglement also raises philosophical questions about the nature of reality – it blurs the boundary between “separate” objects and challenges our intuitions of locality. But from an engineer’s perspective, entanglement is also just another phenomenon to be tamed and utilized. The narrative of quantum technology is one of turning quantum quirks into quantum capabilities. Where classical engineers use wires and signals, quantum engineers use entanglement and superposition. It’s telling that entanglement is often called the “essence” or “cornerstone” of quantum mechanics – crack it, and you unlock a whole new paradigm of information processing.

Newly discovered quantum state revolutionizes material science

The Princeton researchers built their devices with great care. Along with former postdoctoral fellow Qi Zhang, they created ultra-clean samples and chilled them using liquid helium. They measured how the material reacted when exposed to circularly polarized mid-infrared light, at wavelengths around 10.6 microns. They observed a strong response when the light’s spin matched the material’s internal chiral state—a sign of a phenomenon called the circular photogalvanic effect (CPGE).

The CPGE has become a powerful tool in recent years. It works by measuring how electric currents change depending on the direction of light spin. In this case, the presence of a CPGE signal directly proved that the material’s internal structure was chiral. Even more, the direction and pattern of the signal revealed which symmetries had been broken.

The discovery puts to rest years of debate among physicists. Since 2021, there’s been disagreement over whether the charge-ordered state in KV₃Sb₅ actually breaks key symmetries or if those effects were caused by noise or imperfections. Earlier tools like scanning tunneling microscopes and electrical measurements had shown hints of chirality, but results were unclear and often contradicted each other.

/* */