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Why does life prefer one ‘hand’ over the other? New study points to electron spin

A team of scientists has identified a new physical mechanism that could help explain one of the most persistent mysteries in science: why life consistently uses one “handed” version of its molecules and not the other. In a new study led by Prof. Yossi Paltiel of the Center for Nanoscience and Nanotechnology at Hebrew University and Prof. Ron Naaman of the Weizmann Institute, researchers show that electron spin, a fundamental quantum property, can cause mirror-image molecules to behave differently during dynamic processes, even though they are otherwise identical. The work appears in Science Advances.

Many molecules essential to life come in two mirror-image forms, known as enantiomers. Chemically, these forms are nearly indistinguishable. Yet in living systems, only one version is typically used: amino acids are almost exclusively one type, while sugars follow the opposite pattern.

This phenomenon, known as homochirality, has puzzled scientists for more than a century. Existing explanations have struggled to account for why one specific version was selected globally.

Put a nanodiamond under intense pressure and it becomes flexible

Diamond is among the hardest naturally occurring substances on Earth, but if you shrink it down to the nanoscale, it is surprisingly elastic. And that could be useful for a host of applications such as quantum computing. In a paper published in the journal Physical Review X, Chongxin Shan at Zhengzhou University in China and colleagues studied diamonds as small as four nanometers across to see how they respond to pressure.

Scientists already know that nanodiamonds, which are thousands of times smaller than a grain of sand, can survive being stretched or squeezed in ways that destroy a regular diamond. But nobody knew how.

So the team placed individual nanodiamonds (ranging from 4 to 13 nanometers across) inside a transmission electron microscope between two diamond indenters and compressed them. These were connected to a sensor that measured how strongly each nanodiamond resisted being squeezed while a high-resolution camera imaged diamond atoms as they moved. The researchers backed up their observations with computer simulations.

Tiny ‘light-concentrating’ particles boost terahertz technology, study shows

Scientists have found a way to boost terahertz technology using particles thousands of times smaller than a grain of sand. Research published in Scientific Reports by Loughborough University’s Emergent Photonics Research Center shows how a sparse layer of nanoparticles can make materials that produce terahertz radiation more efficient.

Terahertz radiation sits between microwaves and infrared on the electromagnetic spectrum and has a range of potential uses. It can “see” through materials like clothing or plastic and detect chemical fingerprints, with applications in security screening, medical imaging, materials testing, and wireless communications.

But existing devices are limited by how efficiently they can generate terahertz waves.

Laser bursts flip nanoscale magnetic vortices at blistering speeds, opening a path to brain-like spintronics

Spintronics are devices that operate leveraging the spin, an intrinsic form of angular momentum, of electrons. The ability to switch magnetic states is central to the functioning of these devices, as it ultimately allows them to represent binary digits (i.e., “0” and “1”) when processing or storing information.

Some of these devices rely on magnetic vortices, nanoscale whirlpool-like patterns of magnetization that influence the alignment of spins. These vortices possess a property known as helicity, which is essentially the direction in which they rotate.

Reliably switching the helicity of magnetic vortices could open new possibilities for both neuromorphic computing systems, devices that mimic the brain’s neural organization, and multi-state memories. So far, however, this has proved challenging, mainly because it requires a synchronized wave-like rotation of spins without disrupting the geometric structure of vortices.

Sprinkling nanoparticles on spintronics

Today, I want to walk you through a deceptively simple innovation from the lab at Loughborough University (PI: Prof Marco Peccianti): what happens when we decorate a spintronic heterostructure with a sparse layer of plasmonic nanoparticles? This isn’t just a lab curiosity—it’s a step toward making terahertz sources more efficient, compact, and practical for real-world applications like high-speed communications, noninvasive imaging, and advanced spectroscopy.

Spintronic terahertz emitters rely on a thin, multilayer stack—typically heavy metal like tungsten (W), a ferromagnetic layer such as iron (Fe), and a platinum (Pt) cap. A femtosecond laser pulse strikes the structure, rapidly heating electrons and generating a pure spin current through spin-orbit torque effects.

This spin current converts into broadband terahertz radiation at the interfaces, bypassing the need for cumbersome phase-matching crystals used in traditional optical rectification. It’s elegant and scalable, but most laser light reflects off or transmits through without effectively coupling to the magnetic layer, limiting spin injection and THz output power.

A hidden property of light could power future nanomachines

Light does more than illuminate the world—it can also push and twist matter. It was back in the 1870s that James Clerk Maxwell first predicted that light carries momentum and can exert pressure on objects. Nearly a century later, in the 1970s, Arthur Ashkin asked why not use this property of light to hold and push around tiny particles. He developed optical tweezers that use focused laser beams to trap and move nanoscale objects.

While scientists have long known that light can exert small forces, detecting them has been extremely difficult. Objects at this scale are constantly jostled by random thermal motion, making the subtle influence of light hard to measure.

Generalized optical meta-spanners empower arbitrary light paths for multitasking optical manipulation

Have you ever wished to drive microscopic matter along an arbitrarily tailored trajectory instead of just a circle? That’s exactly what we set out to achieve.

The field of photonic force manipulation has opened new avenues for controlling the microscopic world with light. Since the invention of optical tweezers in 1986, the non-contact trapping and manipulation of microscopic particles using the momentum and angular momentum of light has become an indispensable tool in biophysics, soft matter science, and micro-nanotechnology—a contribution recognized by the 2018 Nobel Prize in Physics.

Conventional optical tweezers rely on the intensity gradient of a Gaussian beam to generate a three-dimensional restoring potential for stable particle trapping.

How nanomedicine gets inside your cells and treats you from the inside out

Canadians swallow millions of pills every day to treat common health issues like high blood pressure, high cholesterol and Type II diabetes, but scientists are working at the molecular level to turn patients’ cells into pharmacies.

Nanotechnology, where atoms and molecules are manipulated on a tiny scale—a billion times smaller than a meter—is already incorporated into everyday products like sunscreen, waterproof clothing and smartphones.

In nanomedicine, it’s being used to prompt RNA to make protein-based drugs to treat diseases. Now we can fine-tune protein production by dialing it up or down, creating personalized medicine on an invisible scale.

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