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Growth strategy enhances efficiency and stability of perovskite solar cells

Photovoltaics (PVs), technological systems that can convert sunlight into electricity are among the most promising and widely adopted clean energy solutions worldwide. While existing silicon-based solar cells have already achieved remarkable performances, energy engineers have been working to develop other photovoltaic technologies that could be even more durable, efficient and affordable.

An emerging type of solar cells that could be manufactured at a lower cost, while still retaining good efficiencies, are those based on a class of materials with a characteristic arrangement of atoms, known as perovskites. These cells, known as perovskite solar cells (PSCs), have been found to attain high power conversion efficiencies and are based on materials that could be easier to synthesize when compared to silicon wafers.

Despite their potential, PSCs still face considerable limitations that have so far prevented their widespread deployment and commercialization. Most notably, improving the efficiency of these cells has been found to adversely impact their stability over time, and vice versa.

The AI breakthrough that uses almost no power to create images

From creating art and writing code to drafting emails and designing new drugs, generative AI tools are becoming increasingly indispensable for both business and personal use. As demand increases, they will require even more computing power, memory and, therefore, energy. That’s got scientists looking for ways to reduce their energy consumption.

In a paper published in the journal Nature, Aydogan Ozcan, from the University of California Los Angeles, and his colleagues describe the development of an AI image generator that consumes almost no power.

AI image generators use a process called diffusion to generate images from text. First, they are trained on a large dataset of images and repeatedly add a statistical noise, a kind of digital static, until the image has disappeared.

Two new methods push graphene’s electronic quality beyond traditional semiconductors

Graphene, a single sheet of carbon atoms arranged in a honeycomb lattice, is known for its exceptional strength, flexibility and conductivity. However, despite holding the world record for room-temperature electron mobility, graphene’s performance at cryogenic temperatures has remained below that of the best gallium arsenide (GaAs)-based semiconductor systems, which have benefited from many decades of refinement.

One key obstacle is electronic disorder. In practical devices, is highly sensitive to stray electric fields from charged defects in surrounding materials. These imperfections create spatial fluctuations in , known as electron-hole puddles, that scatter electrons and limit mobility. This disorder has prevented graphene from realizing its full potential as an ultra-clean electronic system.

Now, in two parallel studies, researchers from the National University of Singapore (NUS) and The University of Manchester (UK) report distinct strategies that finally push graphene past this long-standing benchmark. The results set new records for electron mobility, matching and in some cases surpassing GaAs in both transport and quantum mobility, and enabling the observation of quantum effects in unprecedented conditions.

Minimal 3D model reveals fundamental mechanisms behind toughening of soft–hard composites

Engineers have long grappled with a fundamental challenge: creating materials that are both strong and tough enough to resist deformation and prevent fractures. These two properties typically exist in opposition, as materials that excel in one area often fail in the other.

Nature, however, has elegantly solved this trade-off in like bone, teeth, and nacre, which strategically combine soft and hard components in multi-layered architectures. These blueprints have inspired scientists to develop artificial soft–hard composites—from advanced dual-phase steels to specialized gels and reinforced rubbers—that demonstrate performance exceeding that of their individual components.

While artificial soft–hard composites have shown impressive performance in and , the fundamental mechanisms behind their enhanced properties remain largely unclear. The inherent complexity of these materials, encompassing nonlinear behaviors, intricate internal structures, and multi-scale interactions, has made it difficult to isolate the essential design principles.

Engineers send quantum signals with standard Internet Protocol

In a first-of-its-kind experiment, engineers at the University of Pennsylvania brought quantum networking out of the lab and onto commercial fiber-optic cables using the same Internet Protocol (IP) that powers today’s web.

Reported in Science, the work shows that fragile quantum signals can run on the same infrastructure that carries everyday online traffic. The team tested their approach on Verizon’s campus fiber-optic network.

The Penn team’s tiny “Q-chip” coordinates quantum and classical data and, crucially, speaks the same language as the modern web. That approach could pave the way for a future “quantum internet,” which scientists believe may one day be as transformative as the dawn of the online era.

A low-cost protocol enables preparation of magic states and fault-tolerant universal quantum computation

Quantum computers, systems that perform computations leveraging quantum mechanical effects, could outperform classical computers in some optimization and information processing tasks. As these systems are highly influenced by noise, however, they need to integrate strategies that will minimize the errors they produce.

One proposed solution for enabling fault-tolerant quantum computing across a wide range of operations is known as state . This approach consists of preparing special quantum states (i.e., magic states) that can then be used to perform a universal set of operations. This allows the construction of a universal quantum computer—a device that can reliably perform all operations necessary for implementing any quantum algorithm.

Yet while magic state distillation techniques can achieve good results, they typically consume large numbers of error-protected qubits and need to perform many rounds of error correction. This has so far limited their potential for real-world applications.

How an in-between quantum state could boost future technologies

Kai Sun of the University of Michigan is a humble physics professor with ambitious goals. “I’m mainly a paper-and-pencil type of theorist, doing analytical calculations mostly,” Sun said. “My interests are pretty broad, but basically searching for new fundamental principles and new phenomena, especially new phenomena and new physics previously believed to be impossible.”

How a superfluid simultaneously becomes a solid

In everyday life, all matter exists as either a gas, liquid, or solid. In quantum mechanics, however, it is possible for two distinct states to exist simultaneously. An ultracold quantum system, for instance, can exhibit the properties of both a fluid and a solid at the same time.

The Synthetic Quantum Systems research group at Heidelberg University has now demonstrated this phenomenon using a new experimental approach, by feeding a small amount of energy into a superfluid. They showed that, in a driven quantum system of this kind, propagate at two different speeds, which points toward coexisting liquid and solid states, a hallmark of supersolidity. The work is published in the journal Nature Physics.

This surprising and seemingly contradictory behavior of two states of matter existing at the same time does not occur at room temperature. But at ultralow temperatures, takes over, and matter can exhibit fundamentally different properties. When atoms are cooled to such low temperatures, their wave-like nature is dominant. If brought close enough together, many particles merge into one large wave, known as a Bose-Einstein condensate. This state is a superfluid, a fluid that flows without friction.

Physicists observe an elusive form of the Hall effect for the first time

A giant anomalous Hall effect (AHE) has been observed in a nonmagnetic material for the first time, as reported by researchers from Japan. This surprising result was achieved using high-quality Cd3As2 thin films, a Dirac semimetal, under an in-plane magnetic field. By modulating the material’s band structure, the team isolated the AHE and traced its origin to orbital magnetization rather than spin, challenging long-held assumptions in condensed matter physics.

In 1879, American physicist Edwin Hall discovered that a voltage develops across a conductor when it carries an in a , caused by the sideways deflection of moving charges. This phenomenon, which later became known as the Hall effect, quickly became a hot topic in the field and led to notable advances in the theoretical, experimental, and practical realms alike. Soon after the initial discovery of the Hall effect, scientists noticed that exhibited a similar phenomenon—this was coined the anomalous Hall effect (AHE).

Much more puzzling than the ordinary Hall effect, the AHE has stirred up debate among physicists for decades regarding the true nature of its origin. Some theoretical predictions have even hinted that AHE may be possible even in nonmagnetic materials. However, experimental confirmation of these predictions had never been achieved—until now.

Clever algorithm enables real-time noise mitigation in quantum devices

Quantum researchers have deployed a new algorithm to manage noise in qubits in real time. The method can be applied to a wide range of different qubits, even in large numbers.

Noise is the “ghost in the machine” in the effort to make work. Certain quantum devices use qubits—the central component of any quantum processor—and they are extremely sensitive to even small disturbances in their environment.

A collaboration between researchers from the Niels Bohr Institute, MIT, NTNU, and Leiden University has now resulted in a method to effectively manage the noise. The result has been published in PRX Quantum.

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