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Time crystals realized in the so-called quasiperiodic regime hold promise for future applications in quantum computing and sensing.

In ordinary crystals, atoms or molecules form a repeating pattern in space. By extension, in quantum systems known as time crystals, particles form a repeating pattern in both space and time. These exotic systems were predicted in 2012 and first demonstrated in 2016 (see Viewpoint: How to Create a Time Crystal). Now Chong Zu at Washington University in St. Louis and his colleagues have experimentally realized a new form of time crystal called a discrete-time quasicrystal [1]. The team suggests that such states could be useful for high-precision sensing and advanced signal processing.

Conventional time crystals are created by subjecting a collection of particles to an external driving force that is periodic in time. Zu and his colleagues instead selected a quasiperiodic drive in the form of a structured but nonrepeating sequence of microwave pulses. The researchers applied this quasiperiodic drive to an ensemble of strongly interacting spins associated with structural defects, known as nitrogen-vacancy centers, in diamond. They then tracked the resulting dynamics of these spins using a laser microscope.

A new optical amplifier is changing the game. Unlike conventional amplifiers, this chip-based breakthrough leverages optical nonlinearity rather than rare-earth elements, allowing signals to strengthen themselves. The result? A compact, high-performance device with a bandwidth three times wider than traditional solutions.

Expanding the Limits of Optical Amplification

Modern communication networks rely on optical signals to transmit massive amounts of data. However, like weak radio signals, these optical signals need amplification to travel long distances without degrading. For decades, erbium-doped fiber amplifiers (EDFAs) have been the standard solution, extending transmission range without requiring frequent signal regeneration. Despite their effectiveness, EDFAs operate within a limited spectral range, restricting the growth of optical networks.

Proteins are long molecules that must fold into complex three-dimensional structures to perform their cellular functions. This folding process occasionally goes awry, resulting in misfolded proteins that, if not corrected, can potentially lead to disease. Now, a new study has described a potential mechanism that could help explain why some proteins refold in a different pattern than expected.

The researchers, led by chemists at Penn State, found that a type of misfolding, in which the proteins incorrectly intertwine their segments, can occur and create a barrier to the normal folding process. Correcting this misfold requires high-energy or extensive unfolding, which slows the folding process, leading to the unexpected pattern first observed in the 1990s.

“Misfolded proteins can malfunction and lead to disease,” said Ed O’Brien, professor of chemistry in the Eberly College of Science, a co-hire of the Institute for Computational and Data Sciences at Penn State, and leader of the research team. “So, understanding the mechanisms involved in the folding process can potentially help researchers prevent or develop treatments for diseases caused by misfolding.”

Scientists have devised a way to store and read data from individual atoms embedded in tiny crystals only a few millimeters in size (where 1 mm is 0.04 inches). If scaled up, it could one day lead to ultra-high density storage systems capable of holding petabytes of data on a single disc — where 1 PB is equivalent to approximately 5,000 4K movies.

Encoding data as 1s and 0s is as old as the entire history of computing, with the only difference being the medium used to store this data — moving from vacuum tubes flashing on and off, tiny electronic transistors, or even compact discs (CDs), with pits in the surface representing 1s and smoothness indicating 0.

Battery waste has become an increasing problem in recent years due to the massive demand for consumer electronics like smartphones and laptops, as well as the electrification of the automotive industry.

A recent report from Stanford University in the US, published in the journal Nature Communications, found that recycling lithium-ion batteries is far more environmentally friendly than mining for new materials.

In research inspired by the principles of quantum mechanics, researchers from Pompeu Fabra University (UPF) and the University of Oxford reveal new findings to understand why the human brain is able to make decisions quicker than the world’s most powerful computer in the face of a critical risk situation. The human brain has this capacity despite the fact that neurons are much slower at transmitting information than microchips, which raises numerous unknown factors in the field of neuroscience.

The research is published in the journal Physical Review E.

It should be borne in mind that in many other circumstances, the human brain is not quicker than technological devices. For example, a computer or calculator can resolve mathematical operations far faster than a person. So, why is it that in critical situations—for example, when having to make an urgent decision at the wheel of a car—the human brain can surpass machines?

UCLA doctoral student Yilin Wong noticed that some tiny dots had appeared on one of her samples, which had been accidentally left out overnight. The layered sample consisted of a germanium wafer topped with evaporated metal films in contact with a drop of water. On a whim, she looked at the dots under a microscope and couldn’t believe her eyes. Beautiful spiral patterns had been etched into the germanium surface by a chemical reaction.

Wong’s curiosity led her on a journey to discover what no one had seen before: Hundreds of near-identical spiral patterns can spontaneously form on a centimeter square germanium chip. Moreover, small changes in experiment parameters, such as the thickness of the metal film, generated different patterns, including Archimedean spirals, logarithmic spirals, lotus flower shapes, radially symmetric patterns and more.

The discovery, published in Physical Review Materials, occurred fortuitously when Wong made a small mistake while attempting to bind DNA to the metal film.

Researchers have advanced a decades-old challenge in the field of organic semiconductors, opening new possibilities for the future of electronics. The researchers, led by the University of Cambridge and the Eindhoven University of Technology, have created an organic semiconductor that forces electrons to move in a spiral pattern, which could improve the efficiency of OLED displays in television and smartphone screens, or power next-generation computing technologies such as spintronics and quantum computing.

The semiconductor they developed emits circularly polarized light—meaning the light carries information about the ‘handedness’ of electrons. The internal structure of most inorganic semiconductors, like silicon, is symmetrical, meaning electrons move through them without any preferred direction.

However, in nature, molecules often have a chiral (left-or right-handed) structure: like human hands, are mirror images of one another. Chirality plays an important role in like DNA formation, but it is a difficult phenomenon to harness and control in electronics.

Instantly turning a material from opaque to transparent, or from a conductor to an insulator, is no longer the stuff of science fiction. For several years now, scientists have been using lasers to control the properties of matter at extremely fast rates: during one optical cycle of a light wave. But because these changes occur on the timescale of attoseconds—one-billionth of one-billionth of a second—figuring out how they unfold is extremely difficult.

In a new study published in Nature Photonics, Prof. Nirit Dudovich’s team from the Weizmann Institute of Science presents an innovative method of tracking these rapid material changes. This advance in attosecond science, the study of the fastest phenomena in nature, could have a wide variety of future applications, paving the way for ultrafast communications and computing.

If you have ever seen a rainbow, you’ve seen a practical demonstration of how light slows down and is refracted when it passes through matter, in this case, raindrops. Sunlight is composed of a broad spectrum of colors, each of which experiences a different delay as it passes through the droplets. These differences cause the colors to become separated, producing a radiant rainbow.

A major breakthrough in organic semiconductors.

Semiconductors are materials with electrical conductivity that falls between conductors and insulators, making them essential for modern electronics. They are typically crystalline solids, the most common of which is silicon, used extensively in the production of electronic components such as transistors and diodes. Semiconductors are unique because their conductivity can be altered and controlled through doping—adding impurities to the material to change its electrical properties. This property allows them to serve as the foundation for integrated circuits and microchips, powering everything from computers and smartphones to advanced medical devices and renewable energy technologies. The behavior of semiconductors is also crucial in the development of various electronic, photonic, and quantum devices.