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In search of a room-temperature superconductor, scientists present a research agenda

The search for materials that can conduct electricity at room temperature without losing energy is one of the greatest and most consequential challenges of modern physics: loss-free power transmission, more efficient motors and generators, more powerful quantum computers, cheaper MRI devices. Hardly any other material discovery has the potential to change so many areas of technology and everyday life at the same time.

An international research team, with the participation of Christoph Heil from the Institute of Theoretical and Computational Physics at Graz University of Technology (TU Graz) is now presenting a systematic approach to finding such materials. In a perspective article in the journal Proceedings of the National Academy of Sciences, a strategy paper that assesses the current state of research and sets out future directions, the 16 authors state that there are no fundamental physical laws that rule out superconductivity at ambient temperature.

Nanosecond light-by-light switching achieved in liquid crystal droplet

Controlling light with light is a long-sought goal for computing and communication technologies. Achieving this capability would allow optical signals to be processed without converting them into electrical signals, potentially enabling faster and more energy-efficient devices. In recent years, researchers have begun exploring an unexpected platform for this purpose: soft matter.

Soft-matter photonics investigates how materials such as liquids, liquid crystals, gels, and polymers can self-organize into structures that manipulate light. Unlike conventional solid-state photonic components, which require precise nanofabrication, soft materials can spontaneously form functional optical geometries. Some soft materials also exhibit nonlinear optical behavior. For example, through the Kerr effect, their refractive index can change in response to intense light, enabling one beam to influence another and allowing ultrafast optical switching on picosecond timescales.

As reported in Advanced Photonics, an international team of researchers introduced a different approach: a nanosecond optical switch based on resonant stimulated-emission depletion (STED) in a liquid crystal cavity. Rather than relying on refractive index changes, this method manipulates the stored optical energy inside a resonant structure.

Superconductivity controlled by a built-in light-confining cavity

For the first time, physicists have demonstrated that a material’s superconductivity can be altered by coupling it to an in-built, light-confining cavity. In experiments published in Nature, a team led by Itai Keren at Columbia University show how quantum properties can be deliberately engineered by bonding carefully chosen materials together—without applying any external light, pressure, or magnetic field.

As researchers have probed the quantum behavior of solids in ever greater detail, they have uncovered a wealth of so-called “emergent” properties, which arise from intricate interactions between electrons, quantum spins, and localized vibrations of a crystal lattice. Phenomena including superconductivity, magnetism, and charge ordering all emerge from these kinds of collective effects—all richer and more complex than the sum of their microscopic parts.

Building on this principle, physicists are increasingly exploring whether materials could be designed with specific emergent behaviors built directly into their structures. Rather than tuning a compound after it is made, the goal here is to engineer its quantum environment from the outset.

Quantum entanglement offers route to higher-resolution optical astronomy

Researchers in the US have demonstrated how quantum entanglement could be used to detect optical signals from astronomical sources at the single-photon level. Published in Nature, a team led by Pieter-Jan Stas at Harvard University showed how extremely weak light signals could be detected across a fiber link spanning more than 1.5 km—possibly paving the way for optical telescopes with unprecedented resolution.

Interferometry is often used in astronomy to produce high-resolution images of distant objects. By combining light collected across networks of spatially separated detectors, the technique can achieve resolutions comparable to those of a single telescope with a diameter equivalent to the distance between them. In continent-spanning networks like the Event Horizon Telescope, it was used to create the first direct image of a black hole (Messier 87) in 2019.

‘Mesoscale’ swimmers could pave way for drug delivery robots inside the body

In physics, the mesoscale lies between the microscopic and the macroscopic. It is not just the domain of tiny living creatures like small larvae, shrimp, and jellyfish, but also where physics equations become extreme. While the macroscopic realm is governed by inertia and the microscopic by viscosity, the mesoscale is both and neither, requiring a new set of physics to describe it.

Now, physicists at Aalto University’s Department of Applied Physics have discovered how organisms swim in the mesoscale mix of viscosity and inertia. The study was recently published in the journal Communications Physics.

Led by Assistant Professor Matilda Backholm, the multidisciplinary team found the key to efficient swimming in this realm is not just moving faster or growing bigger, but a phenomenon of non-reciprocal motion known as time reversal symmetry breaking. The results help fill a knowledge gap in fundamental physics and could pave the way for applications such as mesorobotics; tiny robots injected inside a patient’s body for drug delivery or carrying out medical procedures.

Nearby red dwarf star hosts at least four planets—with one in the habitable zone

In 2020, a study confirmed that two planets orbited the nearby red dwarf, GJ 887. Now, astronomers have confirmed the existence of two additional planets orbiting GJ 887 in a new study published in Astronomy and Astrophysics. The new study suggests that one of these newly confirmed planets is in the habitable zone.

GJ 887 is a bright red dwarf star about 10.7 light years away from our solar system—a relatively short distance compared to other star systems. The previous study showed two non-transiting exoplanets with short orbital periods of 9 and 21 days and a potential third planet with a period of 50 days. At the time, available data could not differentiate whether the signal that was interpreted as potentially being from the third planet was coming from a planet or magnetic activity from the star.

Red dwarf stars are prime targets for finding low-mass planets in the habitable zone (HZ)—a region within a particular distance from a star where a planet’s surface temperature allows for the existence of liquid water. The team involved in the new study aimed to determine whether this potential third planet could be confirmed and whether there might be any additional planets.

2D topological Kondo insulator observed in a moiré superlattice

When mobile charge carriers, also known as itinerant electrons, interact with the strong exchange magnetic fields associated with the intrinsic angular momentum of localized electrons, this can give rise to the so-called Kondo effect. A Kondo insulator is a state of matter with an energy gap opened by the Kondo effect that forbids electrical conduction at low temperatures.

Like Kondo insulators, topological Kondo insulators are materials that behave as insulators (i.e., not conducting electricity) in their interior, but, unlike their counterparts without topology, can conduct electricity at their surface or edges. This unique, quantum phase of matter is protected by a material’s internal symmetry and topology; thus, it is not easily disrupted.

So far, hints of this phase have been primarily observed in 3D quantum materials, such as samarium hexaboride (SmB₆) and ytterbium dodecaboride. Some physicists and material scientists have also been exploring the possible existence of this phase in 2D structures comprised of two materials stacked with a slight mismatch between them, producing a pattern known as a moiré superlattice.

Robotic microfluidic platform brings AI to lipid nanoparticle design

AI has designed candidate drugs for antibiotic-resistant infections and genetic diseases. But efforts to incorporate AI into the design of lipid nanoparticles (LNPs), the revolutionary delivery vehicles behind mRNA therapies like the COVID-19 vaccines, have been much more limited.

Designing LNPs is especially challenging: Each formulation combines multiple lipid components whose ratios influence how the particle delivers genetic instructions inside cells. Scientists still lack a clear map connecting those chemical inputs to biological outcomes.

The reason? There simply isn’t enough data.

Multi-wavelength observations track bright gamma-ray blazar’s three-year cycle

By analyzing the data from various space observatories and ground-based telescopes, European astronomers have performed a multiwavelength study of a bright gamma-ray blazar known as S5 1044+71. The new study, published Feb. 26 on the arXiv pre-print server, delivers a comprehensive view of this blazar, which could help us better understand its nature.

Blazars are very compact quasi-stellar objects (quasars) associated with supermassive black holes (SMBHs) at the centers of active, giant elliptical galaxies. They are the most luminous and extreme subclass of active galactic nuclei (AGNs). The characteristic features of blazars are highly collimated relativistic jets pointed almost exactly toward Earth.

Astronomers divide blazars into two classes, based on their optical emission properties: flat-spectrum radio quasars (FSRQs) that feature prominent and broad optical emission lines, and BL Lacertae objects (BL Lacs), which do not.

Mapping 3D-super-enhancers with machine learning to pinpoint regulators of cell identity

Scientists usually study the molecular machinery that controls gene expression from the perspective of a linear, two-dimensional genome—even though DNA and its bound proteins function in three dimensions (3D). To better understand how key components of this machinery, such as super-enhancers, regulate genes in this 3D reality, scientists at St. Jude Children’s Research Hospital have developed a new algorithm called BOUQUET.

Using machine learning, BOUQUET reveals that sets of genes and their regulatory elements can interact within protein condensates, high-density membraneless droplets, in cells’ nuclei. The findings, which provide new insight into how cells regulate the genes that control their specialized identities, were published today in Nucleic Acids Research.

Cells express certain sets of genes to carry out specific functions; for example, a blood cell and a brain cell express different context-specific genes. There are 3 billion base pairs of human DNA, and the genes involved in cell identity are scattered throughout. Even more challenging, enhancers, DNA elements that activate gene expression, can be thousands of DNA bases away from their target genes.

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