Thin-film lithium niobate is an emerging nonlinear integrated photonics platform ideally suited for quantum applications. Through spontaneous parametric down-conversion (SPDC), it can generate correlated photon pairs for quantum key distribution, teleportation, and computing.
Quantum memory lets a quantum computer perform a task not necessarily with fewer steps, but with less data. Could this in itself be a way to prove quantum advantage?
The new papers show that quantum memory lets a quantum computer perform a task not necessarily with fewer steps, but with less data. As a result, researchers believe this in itself could be a way to prove quantum advantage. “It allows us to, in the more near term, already achieve that kind of quantum advantage,” said Hsin-Yuan Huang, a physicist at Google Quantum AI.
But researchers are excited about the practical benefits too, as the new results make it easier for researchers to understand complex quantum systems.
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A mathematical study finds that three definitions of what it means for entropy to increase, which have previously been considered equivalent, can produce different results in the quantum realm.
Bell’s theorem, the well-known theoretical framework introduced by John Bell decades ago, delineates the limits of classical physical processes arising from relativistic causality principles. These are principles rooted in Einstein’s theory of relativity, which dictate how cause and effect operate in the universe.
Advancements in quantum information technology are paving the way for faster and more efficient data transfer. A key challenge has been ensuring that qubits, the fundamental units of quantum information, can be transferred between different wavelengths without losing their essential properties, such as coherence and entanglement.
Many scientists are studying different materials for their potential use in quantum technology. One important feature of the atoms in these materials is called spin. Scientists want to control atomic spins to develop new types of materials, known as spintronics. They could be used in advanced technologies like memory devices and quantum sensors for ultraprecise measurements.
In a recent breakthrough, researchers at the U.S. Department of Energy’s (DOE) Argonne National Laboratory and Northern Illinois University discovered that they could use light to detect the spin state in a class of materials called perovskites (specifically in this research methylammonium lead iodide, or MAPbI3). Perovskites have many potential uses, from solar panels to quantum technology.
The work is published in the journal Nature Communications.
CAMBRIDGE, England, Oct. 15, 2024 — Nu Quantum has announced a proof-of-principle prototype that advances the development of modular, distributed quantum computers by enabling connections across different qubit modalities and providers. The technology, known as the Qubit-Photon Interface, functions similarly to Network Interface Cards (NICs) in classical computing, facilitating communication between quantum computers over a network and supporting the potential growth of quantum infrastructure akin to the impact NICs have had on the Cloud and AI markets.
For quantum computers to achieve practical applications—such as accurately simulating atomic-level interactions—they must scale to 1,000 times their current size. This will require a shift from single quantum processing units (QPUs) to distributed quantum systems composed of hundreds of interconnected QPUs, operating at data center scale, similar to cloud and AI supercomputers.
The efficient transfer of quantum information between matter and light at the quantum level is the biggest challenge to scaling quantum computers, and this is the specific issue that the QPI addresses.
An international team of scientists, composed of researchers from the Complutense University of Madrid, Saint Louis University’s Madrid campus, and the University of California, has proposed a new theory suggesting that spacetime could be made up of “entangled virtual bosons”, similar to the double helix of DNA. This finding, which could have significant implications for the unification of gravity and electromagnetism, was recently published in the journal General Relativity and Gravity.
The research was led by Professor Robert Monjo, who holds a PhD in physics and mathematics from Saint Louis University’s Madrid campus, in collaboration with Professor Rutwig Campoamor-Stursberg, head of the Department of Algebra, Geometry, and Topology at the Complutense University of Madrid, and researcher Álvaro Rodríguez-Abella from the University of California, Los Angeles. According to the authors, their work represents an important step forward in understanding the true nature of spacetime. Monjo states: Up until now, there has been a significant gap between gravity and the other forces of nature, but with this study, we have found a link that could unite them.
One of the key aspects of this study lies in the extension of the idea of “color” symmetry—a concept from quantum chromodynamics—applied to gravity. This approach could allow gravity and electromagnetism to be interpreted as manifestations of a more general theory. Symmetries, defined as invariances of observed quantities under different transformations, are fundamental to understanding modern physics. In this case, the researchers have generalized these symmetries to propose what they call “colored gravity”, a theory that expands on Einstein’s ideas about gravity.
Researchers used ultra-thin NbOCl₂ to generate entangled photon pairs for quantum computing, potentially shrinking components.
A study in Nature Physics has realized a dual-species Rydberg array combining rubidium (Rb) and cesium (Cs) atoms to enhance quantum computing and its applications.
