Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: quantum physics – Page 26

Turning a quantum battery’s environmental sensitivity into an advantage

Quantum batteries, devices that store energy by exploiting quantum mechanical phenomena, could, in principle, be charged faster and more efficiently than classical ones. Despite their potential, connecting these batteries to chargers is known to create quantum correlations that can trap some energy inside the combined battery-charger system. This can reduce useful work, or the energy available to complete a task that can be extracted from the battery alone.

Researchers at the University of Insubria & INFN, University of Genova & CNR-SPIN and University of Milan recently proposed a new design strategy that could potentially increase the usable energy of quantum batteries. Their approach, outlined in a paper in Physical Review Letters, involves connecting both a battery and its charger to a shared environment that is continuously monitored.

“Quantum technologies—including quantum batteries—are usually designed under the assumption that the environment is the enemy,” the authors told Phys.org.

Supramolecular nanofibers paired with nanohole substrate improve exciton transport in organic solid

Self-assembling, anthracene-based supramolecular nanofibers can enable excitons to migrate hundreds of nanometers, according to a new experimental finding by researchers at Science Tokyo. Coupling these nanofibers with a plasmonic gold nanohole substrate further doubles exciton diffusivity. By mitigating the limited diffusivity of singlet excitons in organic semiconductors, this approach offers a new strategy for improving optoelectronic technologies.

For decades, one of the biggest challenges in organic optoelectronics has been the limited diffusivity of excitons. Created when light is absorbed, excitons diffuse through the semiconducting material before they can dissociate into free charge carriers to generate electricity. However, excitons in conventional organic semiconductors typically diffuse only up to 5–20 nm before recombining, limiting the performance of optoelectronic devices.

Now, researchers from the Institute of Science Tokyo (Science Tokyo) in Japan have managed to overcome this long-standing limitation by combining molecular self-assembly with plasmonic nanotechnology. The breakthrough comes from a study conducted by a collaborative research team comprising Professor Martin Vacha and Associate Professor Yoshimitsu Sagara from Science Tokyo and Dr. Takatoshi Fujita from the National Institute for Quantum Science and Technology in Japan. The findings are published in the journal Nano Letters.

Quantum simulators gain quantitative error bars in 51-ion test

In the coming years, increasingly larger and more powerful quantum systems are expected to tackle problems that are difficult or impossible to solve using conventional computers. However, the more powerful quantum simulations become, the more difficult it is to independently verify their results. Where classical simulation is still feasible, results can be cross-checked directly; beyond that regime, other methods are needed.

Researchers led by Tristan Kraft of the Technical University of Munich and Peter Zoller of the University of Innsbruck and the Institute for Quantum Optics and Quantum Information at the Austrian Academy of Sciences, together with Barbara Kraus of the Technical University of Munich, have now demonstrated how a quantum simulator can be experimentally characterized and how the uncertainties that arise in the process can be translated into quantitative error limits for its results.

The approach was demonstrated by a team led by Manoj Joshi and Christian Roos using an ion-trap quantum simulator containing up to 51 ions.

Krypton gas emerges as a new ingredient for quantum computing

To commercialize quantum computing, manufacturers need high-quality superconducting materials for microchips, but they also require a reliable, sustainable nanofabrication process. Tantalum is a corrosion-resistant metal that meets the first criterion but not the second. That’s because it has to be deposited on a substrate at temperatures that typically exceed 400°C (752°F)—too hot for many semiconductor foundries’ current tools.

Cornell researchers have developed a method that uses krypton gas to slash that deposition temperature to 200°C (392°F) while depositing tantalum on silicon, a standard high-quality substrate. The process resulted in thin films that also have substantially higher electronic conductivity.

“Tantalum as a material has been shown to be very exciting from a device performance perspective, but its manufacturability had some question marks because of integration challenges such as required process temperatures,” said Valla Fatemi, assistant professor and Aref and Manon Lahham Faculty Fellow in the Cornell Duffield College of Engineering, who led the project.

A new approach to building noise-resistant quantum sensors

Quantum sensors, devices that collect measurements by exploiting quantum-mechanical phenomena, could potentially detect extremely weak magnetic, gravitational and electromagnetic signals with greater sensitivity than classical sensors. Some quantum sensors leverage entanglement, a phenomenon that prompts distant particles to become so strongly linked that the physical state of one particle dictates the state of the others.

Despite their potential, these sensors are often very sensitive to noise (i.e., external disturbances originating from the surrounding environment). This means that even small environmental disturbances and hardware imperfections can disrupt delicate quantum states and reduce the devices’ sensing precision.

Researchers at the Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area, Southern University of Science and Technology and Shenzhen University recently introduced a new method to develop noise-adaptive sensors that can collect more precise measurements. Their approach, outlined in a paper published in Physical Review Letters, relies on a variational quantum circuit, a sequence of quantum operations that can be adjusted to search for a state that performs well on specific measurement tasks.

New photonic crystal method improves single-photon sources for quantum networks

Quantum communication promises many advantages over today’s standard technologies, including absolutely secure transmission of large amounts of data. However, it requires single photons—and generating them is very difficult. Researchers at the Technical University of Munich (TUM) and the Munich Center for Quantum Science and Technology (MCQST) have developed a new method that overcomes the problems of previous approaches.

Instead of amplifying the desired frequency, the researchers selectively suppress unwanted frequencies. Until now, so-called resonators have mostly been used to produce single photons—tiny optical structures that influence photon sources, causing them to emit light predominantly at a specific frequency. However, these resonators function only within a narrow frequency range and must be precisely tuned to the respective photon source.

Researchers at TUM and MCQST have developed a new approach that takes the opposite route. Instead of causing emitters to emit more light at a specific frequency, they adapt the emitter’s environment so that less light is emitted at unwanted frequencies.

The global race to make a practical quantum computer just took a big leap forward

In the global race to build bigger and better quantum computers, researchers have taken a step forward. A new machine called Helios is radically different from other quantum computers.

Quantum computers harness the power of quantum mechanics, the laws that govern physics at atomic and subatomic scales. Among various designs for such machines, Helios is a trapped-ion quantum computer, which means it uses charged atoms suspended in free space using electromagnetic fields.

It operates using 98 qubits—the units of information that a quantum computer uses to process data. This number of qubits makes it the largest trapped-ion quantum computer built so far. Quantinuum, the company behind the device, is based in Cambridge, U.K., and Broomfield, Colorado. It demonstrated earlier machines operating on 32 qubits in 2023 and 56 qubits in 2025.

Quantum light engine links atom-photon thermodynamics to classical physics

What is heat, and what is useful work if a machine consists only of an atom and light particles? In modern quantum technologies, this kind of question connects thermodynamics with quantum physics. Researchers at the University of Basel, Switzerland, have developed a theoretical approach that can reconcile both theories.

Anomalous quantum oscillations reveal new physics in a topological insulator

A study has been published in Nature Communications that identifies an unusual regime of quantum oscillations in a three-dimensional topological insulator. The results show that, when subjected to temperatures near absolute zero and extreme magnetic fields, electrons in the material zirconium pentatelluride (ZrTe₅) exhibit behavior that deviates from the pattern predicted by conventional theory.

The study, led by researchers from the University of São Paulo (USP) in Brazil, Los Alamos National Laboratory and the University of Washington, among other U.S. institutions, combines electrical transport experiments conducted in magnetic fields of up to 60 tesla and at temperatures around 0.7 kelvin (−272.45 °C) with detailed theoretical modeling.

“This work expands our understanding of electron transport in exotic phases of matter and suggests that topological insulators support the transport of not only electric charge, but also another fundamental degree of freedom: electron spin,” says Julio Larrea Jiménez, a professor at USP’s Physics Institute (IF) and co-founder and director of the Laboratory for Quantum Matter under Extreme Conditions (LQMEC).

Gluons may play a central role in baryon number conservation—and matter’s stability

New results from the STAR detector at the Relativistic Heavy Ion Collider (RHIC) suggest that gluons, the glue-like particles that hold quarks together inside protons, play a central role in the conservation of baryon number—an essential part of a particle’s quantum identity.