Lifeboat Foundation

Research on superconductivity has taken a significant leap with Princeton Universitys exploration of edge supercurrents in topological superconductors like molybdenum telluride.

Initially elusive, these supercurrents have been observed and enhanced through experiments with niobium, leading to intriguing phenomena such as stochastic switching and anti-hysteresis, altering the understanding of electron behavior in superconductors.

Superconductivity and Topological Materials.

Researchers will be able to analyze chemical compounds and atoms in greater detail than ever before using the brightest, clearest laser of its kind anywhere in the world.

“Tidal heating plays an important role in the heating and orbital evolution of celestial bodies,” said Alex Hayes, professor of astronomy.

“It provides the warmth necessary to form and sustain subsurface oceans in the moons around giant planets like Jupiter and Saturn.”

Researchers at Freie Universität Berlin, University of Maryland and NIST, Google AI, and Abu Dhabi set out to robustly estimate the free Hamiltonian parameters of bosonic excitations in a superconducting quantum simulator. The protocols they developed, outlined in a paper pre-published on arXiv, could contribute to the realization of highly precise quantum simulations that reach beyond the limits of classical computers.

All proteins are composed of chains of amino acids, which generally fold up into compact globules with specific shapes. The folding process is governed by interactions between the different amino acids—for example, some of them carry electrical charges—so the sequence determines the structure. Because the structure in turn defines a protein’s function, deducing a protein’s structure is vital for understanding many processes in molecular biology, as well as for identifying drug molecules that might bind to and alter a protein’s activity.

Protein structures have traditionally been determined by experimental methods such as x-ray crystallography and electron microscopy. But researchers have long wished to be able to predict a structure purely from its sequence—in other words, to understand and predict the process of protein folding.

For many years, computational methods such as molecular dynamics simulations struggled with the complexity of that problem. But AlphaFold bypassed the need to simulate the folding process. Instead, the algorithm could be trained to recognize correlations between sequence and structure in known protein structures and then to generalize those relationships to predict unknown structures.

A rare configuration of seven galaxies aligned behind a galaxy cluster allows researchers to probe with high precision the dark matter distribution within the cluster.

OLED performance depends on the behavior of electron–hole pairs, or excitons, that form within the emissive layer of the device. High efficiencies can be obtained when most of the excitons produce light as they decay, but some excitons can be lost without emitting light through a process known as exciton–polaron quenching (EPQ).

EPQ was believed to occur mainly within the bulk of the emissive layer, but recent studies have suggested that significant quenching can take place at the interface with the adjacent device layers. To isolate this energy-loss channel, the researchers designed a series of bilayer devices that allowed them to identify three physical factors that govern interfacial EPQ in any OLED device. They found that the dominant factor is the effect of the energy barriers experienced by electrons and holes at the interfaces: A barrier higher than about 0.2 eV leads to greater interfacial EPQ, which causes a significant drop in emission efficiency.

Armed with this knowledge the researchers engineered OLED devices to minimize losses from interfacial EPQ, which resulted in efficiency enhancements for red, green, and blue devices of 70%, 47%, and 66%, respectively. The loss mitigation also increased the lifetime of blue OLEDs by as much as 67%, an important result for creating long-lived full-color displays.

Despite its intensity, the gravitational collapse of certain massive stars does not produce an abundance of heavy elements.

About half of the elements heavier than iron are made by the r, or rapid, process. A nucleus captures neutrons so quickly that radioactive decay is forestalled until the neutron-heavy nucleus finally emits electrons and neutrinos and settles at a new, higher atomic number. Besides normal supernovae and neutron-star mergers, the r process is also suspected to occur in so-called collapsars. These are rapidly rotating massive stars that collapse without producing a regular supernova once they exhaust their fuel. However, simulations by Coleman Dean and Rodrigo Fernández of the University of Alberta, Canada, have now undermined that r-process conjecture [1].

A collapsar’s progenitor is massive enough that it forms a black hole. To shed its prodigious angular momentum, it also forms a thick, unstable accretion disk. During the collapse, nuclei in the stellar envelope break apart, and their protons combine with electrons in the envelope to produce neutrons and neutrinos in large numbers. These neutrons could turn the disk into a favorable, if fleeting, site for the r process to forge and disperse heavy elements—provided that this neutron-rich matter can be ejected.

When two laser beams converge on a volume of gas, their interference creates a diffraction grating made of plasma that can divert and shape a third beam.

Once a laser pulse packs more than 10¹⁸ W/cm² or so of power, its electric field strips electrons from atoms and accelerates them to near light speed. This effect could lead to compact and highly efficient particle accelerators (see Viewpoint: Shooting Ahead with Wakefield Acceleration). But for various reasons to do with pulse generation, the main pulse is unavoidably preceded by weaker prepulses, which can muddle an experiment’s initial conditions and frustrate anticipated results. Now Matthew Edwards of Stanford University, working at Julia Mikhailova’s lab at Princeton University, and collaborators have demonstrated a setup that can delete meddlesome prepulses with unprecedented effectiveness [1].

A key component of the researchers’ setup was demonstrated in 2009 [2]. Two pulsed beams of the same wavelength converged on a volume of gas contained in a cell, ionizing the gas where the beams constructively interfered. The difference in refractive index between the plasma and the neutral gas created an instant and switchable diffraction grating.