Photonics integrates quantum mechanics with light, fostering innovations in quantum computing, secure data transfer, and high-resolution imaging techniques.
Category: quantum physics – Page 23
‘Like talking on the telephone’: Quantum computing engineers get atoms chatting long distance
UNSW engineers have made a significant advance in quantum computing: they created ‘quantum entangled states’—where two separate particles become so deeply linked they no longer behave independently—using the spins of two atomic nuclei. Such states of entanglement are the key resource that gives quantum computers their edge over conventional ones.
The research is published in the journal Science, and is an important step toward building large-scale quantum computers—one of the most exciting scientific and technological challenges of the 21st century.
Lead author Dr. Holly Stemp says the achievement unlocks the potential to build the future microchips needed for quantum computing using existing technology and manufacturing processes.
Magnetic tunnel junctions mimic synapse behavior for energy-efficient neuromorphic computing
The rapid development of artificial intelligence (AI) poses challenges to today’s computer technology. Conventional silicon processors are reaching their limits: they consume large amounts of energy, the storage and processing units are not interconnected and data transmission slows down complex applications.
As the size of AI models is constantly increasing and they are having to process huge amounts of data, the need for new computing architectures is rising. In addition to quantum computers, focus is shifting, in particular, to neuromorphic concepts. These systems are based on the way the human brain works.
This is where the research of a team led by Dr. Tahereh Sadat Parvini and Prof. Dr. Markus Münzenberg from the University of Greifswald and colleagues from Portugal, Denmark and Germany began. They have found an innovative way to make computers of tomorrow significantly more energy-efficient. Their research centers around so-called magnetic tunnel junctions (MTJs), tiny components on the nanometer scale.
‘Quantum squeezing’ a nanoscale particle for the first time
Researchers Mitsuyoshi Kamba, Naoki Hara, and Kiyotaka Aikawa of the University of Tokyo have successfully demonstrated quantum squeezing of the motion of a nanoscale particle, a motion whose uncertainty is smaller than that of quantum mechanical fluctuations.
As enhancing the measurement precision of sensors is vital in many modern technologies, the achievement paves the way not only for basic research in fundamental physics but also for applications such as accurate autonomous driving and navigation without a GPS signal. The findings are published in the journal Science.
The physical world at the macroscale, from dust particles to planets, is governed by the laws of classical mechanics discovered by Newton in the 17th century. The physical world at the microscale, atoms and below, is governed by the laws of quantum mechanics, which lead to phenomena generally not observed at the macroscale.
Physicist proves unsolvability beyond one dimension for quantum Ising models
By extending a proof of a physically important behavior in one-dimensional quantum spin systems to higher dimensions, a RIKEN physicist has shown in a new study that the model lacks exact solutions. The research is published in the journal Physical Review B.
Theoretical physicists develop mathematical models to describe material systems, which they can then use to make predictions about how materials will behave.
One of the most important models is the Ising model, which was first developed about a century ago to model magnetic materials such as iron and nickel.
Physicists create new electrically controlled silicon-based quantum device
A team of scientists at Simon Fraser University’s Quantum Technology Lab and leading Canada-based quantum company Photonic Inc. have created a new type of silicon-based quantum device controlled both optically and electrically, marking the latest breakthrough in the global quantum computing race.
The research, published in the journal Nature Photonics, reveals new diode nanocavity devices for electrical control over silicon color center qubits.
The devices have achieved the first-ever demonstration of an electrically-injected single-photon source in silicon. The breakthrough clears another hurdle toward building a quantum computer—which has enormous potential to provide computing power well beyond that of today’s supercomputers and advance fields like chemistry, materials science, medicine and cybersecurity.
Advanced AI links atomic structure to quantum tech
A research team led by Oak Ridge National Laboratory has developed a new method to uncover the atomic origins of unusual material behavior. This approach uses Bayesian deep learning, a form of artificial intelligence that combines probability theory and neural networks to analyze complex datasets with exceptional efficiency.
The technique reduces the amount of time needed for experiments. It helps researchers explore sample regions widely and rapidly converge on important features that exhibit interesting properties.
“This method makes it possible to study a material’s properties with much greater efficiency,” said ORNL’s Ganesh Narasimha. “Usually, we would need to scan a large region, and then several small regions, and perform spectroscopy, which is very time-consuming. Here, the AI algorithm takes control and does this process automatically and intelligently.”
Universal scheme efficiently generates arbitrary two-qubit gates in superconducting quantum processors
The operation of quantum computers, systems that process information leveraging quantum mechanical effects, relies on the implementation of quantum logic gates. These are essentially operations that manipulate qubits, units of information that can exist in a superposition of states and can become entangled.
A type of quantum logic gate that enables the entanglement between qubits is a so-called two-qubit gate. Notably, most existing schemes for generating these gates force qubits outside of the conditions or parameters in which they can best store information and are easier to control.
Researchers at the Beijing Academy of Quantum Information Sciences (BAQIS) and Tsinghua University recently introduced a new universal scheme to implement two-qubit gates in superconducting quantum processors. This scheme, outlined in a paper published in Nature Physics, was found to reliably enable the generation of entanglement between qubits in superconductor-based quantum computers.