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Probing spectral features of quantum many-body systems with quantum simulators

Estimating spectral features of quantum many-body systems has attracted great attention in condensed matter physics and quantum chemistry. To achieve this task, various experimental and theoretical techniques have been developed, such as spectroscopy techniques1,2,3,4,5,6,7 and quantum simulation either by engineering controlled quantum devices8,9,10,11,12,13,14,15,16 or executing quantum algorithms17,18,19,20 such as quantum phase estimation and variational algorithms. However, probing the behaviour of complex quantum many-body systems remains a challenge, which demands substantial resources for both approaches. For instance, a real probe by neutron spectroscopy requires access to large-scale facilities with high-intensity neutron beams, while quantum computation of eigenenergies typically requires controlled operations with a long coherence time17,18. Efficient estimation of spectral properties has become a topic of increasing interest in this noisy intermediate-scale quantum era21.

A potential solution to efficient spectral property estimation is to extract the spectral information from the dynamics of observables, rather than relying on real probes such as scattering spectroscopy, or direct computation of eigenenergies. This approach capitalises on the basics in quantum mechanics that spectral information is naturally carried by the observable’s dynamics10,20,22,23,24,25,26. In a solid system with translation invariance, for instance, the dynamic structure factor, which can be probed in spectroscopy experiments7,26, reaches its local maximum when both the energy and momentum selection rules are satisfied. Therefore, the energy dispersion can be inferred by tracking the peak of intensities in the energy excitation spectrum.

Total synthesis of ibogaine creates new opportunities for studying a psychoactive plant derivative

Ibogaine—a psychoactive plant derivative—has attracted attention for its anti-addictive and anti-depressant properties. But ibogaine is a finite resource, extracted from plants native to Africa like the iboga shrub (Tabernanthe iboga) and the small-fruited voacanga tree (Voacanga africana). Further, its use can lead to irregular heartbeats, introducing safety risks and an overall need to better understand how its molecular structure leads to its biological effects.

In a study appearing in Nature Chemistry, researchers at the University of California, Davis Institute for Psychedelics and Neurotherapeutics (IPN) report the successful of ibogaine, ibogaine analogs and related compounds from pyridine—a relatively inexpensive and widely available chemical.

The team’s strategy enabled the synthesis of four naturally occurring ibogaine-related alkaloids as well as several non-natural analogs. Overall yields ranged from 6% to 29% after only six or seven steps, a marked increase in efficiency from previous synthetic efforts to produce similar compounds.

Rewriting the Rules of Aging: New Chromatin Discovery Challenges Conventional Wisdom

Published in the Journal of the American Chemical Society, the research by scientists at King’s College London and their collaborators suggests that chromatin—the complex of DNA

DNA, or deoxyribonucleic acid, is a molecule composed of two long strands of nucleotides that coil around each other to form a double helix. It is the hereditary material in humans and almost all other organisms that carries genetic instructions for development, functioning, growth, and reproduction. Nearly every cell in a person’s body has the same DNA. Most DNA is located in the cell nucleus (where it is called nuclear DNA), but a small amount of DNA can also be found in the mitochondria (where it is called mitochondrial DNA or mtDNA).

Scientists recode the genome for programmable synthetic proteins

Synthetic biologists from Yale were able to re-write the genetic code of an organism—a novel genomically recoded organism (GRO) with one stop codon—using a cellular platform that they developed enabling the production of new classes of synthetic proteins. These synthetic proteins, researchers say, offer the promise of innumerable medical and industrial applications that can benefit society and human health.

The creation of the landmark GRO, known as “Ochre”—which fully compresses redundant, or “degenerate” codons, into a single codon—is described in a new study published in the journal Nature. A codon is a sequence of three nucleotides in DNA or RNA that codes for a specific amino acid, which serves as the biochemical building blocks for proteins.

“This research allows us to ask fundamental questions about the malleability of genetic codes,” said Farren Isaacs, professor of molecular, cellular and at Yale School of Medicine and of biomedical engineering at Yale’s Faculty of Arts and Sciences, who is co-senior author of the paper. “It also demonstrates the ability to engineer the genetic code to endow multi-functionality into proteins and usher in a new era of programmable biotherapeutics and biomaterials.”

‘The fraud was not subtle’: Chemist blames students after ten papers retracted

While reviewing a manuscript for the Journal of Organic Chemistry, Caroline Kervarc-Genre and her colleague, Thibault Cantat, researchers at the French Alternative Energies and Atomic Energy Commission, noticed something unusual.

The nuclear magnetic resonance (NMR) spectra buried in the supplementary information had striking irregularities: The baseline was interrupted in some parts, and the noise was the same from one spectrum to the next. “Noise being inherently random, repeating noise is only possible if the spectra are altered [or] fake,” Kervarc-Genre told Retraction Watch.

Starting to suspect something was wrong, she and Cantat, examined other papers by the lead author. They discovered data appeared to have been edited in several of the author’s latest publications. “The fraud was not subtle,” Kervarc-Genre said.

Meteorite discovery challenges long-held theories on Earth’s missing elements

Understanding where Earth’s essential elements came from—and why some are missing—has long puzzled scientists. Now, a new study reveals a surprising twist in the story of our planet’s formation.

A new study led by Arizona State University’s Assistant Professor Damanveer Grewal from the School of Molecular Sciences and School of Earth and Space Exploration, in collaboration with researchers from Caltech, Rice University, and MIT, challenges traditional theories about why Earth and Mars are depleted in moderately volatile elements (MVEs).

MVEs like copper and zinc play a crucial role in planetary chemistry, often accompanying life-essential elements such as water, carbon, and nitrogen. Understanding their origin provides vital clues about why Earth became a habitable world. Earth and Mars contain significantly fewer MVEs than primitive meteorites (chondrites), raising fundamental questions about planetary formation.

Unlocking graphite’s potential: Sliding layers for advanced material properties

Can copper be turned into gold? For centuries, alchemists pursued this dream, unaware that such a transformation requires a nuclear reaction. In contrast, graphite—the material found in pencil tips—and diamond are both composed entirely of carbon atoms; the key difference lies in how these atoms are arranged. Converting graphite into diamond requires extreme temperatures and pressures to break and reform chemical bonds, making the process impractical.

A more feasible transformation, according to Prof. Moshe Ben Shalom, head of the Quantum Layered Matter Group at Tel Aviv University, involves reconfiguring the atomic layers of graphite by shifting them against relatively weak van der Waals forces. This study, led by Prof. Ben Shalom and Ph.D. students Maayan Vizner Stern and Simon Salleh Atri, all from the Raymond & Beverly Sackler School of Physics & Astronomy at Tel Aviv University, was recently published in the journal Nature Review Physics.

While this method won’t create diamonds, if the switching process is fast and efficient enough, it could serve as a tiny electronic memory unit. In this case, the value of these newly engineered “polytype” materials could surpass that of both diamonds and gold.

Promising new class of high-temperature superconductors achieves stability at room pressure

Researchers have made a significant step in the study of a new class of high-temperature superconductors: creating superconductors that work at room pressure. That advance lays the groundwork for deeper exploration of these materials, bringing us closer to real-world applications such as lossless power grids and advanced quantum technologies.

Superconductivity, the ability of certain materials to conduct electricity with zero resistance, typically occurs at extremely low temperatures, or in some cases, under high pressures. For decades, researchers have focused on a class of materials called cuprates, known for their ability to achieve superconductivity at relatively high temperatures.

About five years ago, a team of researchers at the Department of Energy’s SLAC National Accelerator Laboratory and Stanford University discovered superconductivity in nickelates, materials chemically similar to cuprates—and last summer, another group of researchers reported superconductivity in a new class of nickel oxides at temperatures comparable to cuprates.

Revolutionizing Displays: Dual-Mode Electrochemical Devices Merge Light and Color

Researchers introduce an innovative device that combines light emission and color control with clay compounds, offering a versatile solution for multifunctional displays.

The field of display technology is on the verge of a major breakthrough, driven by the growing interest in electrochemical stimuli-responsive materials. These materials can undergo rapid electrochemical reactions in response to external stimuli, such as low voltage.

A key advantage of these reactions is their ability to produce different colors almost instantly, paving the way for next-generation display solutions. An electrochemical system consists of electrodes and electrolytes, and researchers have found that integrating luminescent and coloration molecules directly onto the electrodes—rather than within the electrolyte—can significantly enhance efficiency and stability in display devices.

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