Basic science

Researchers from Columbia University, the University of Chicago, the University of Vienna in Austria, Politecnico di Milano in Italy, and Universita Degli Studi Dell’ Aquila in Italy have created a device that can generate photon pairs more efficiently than previous methods while being less prone to error. To create the device, the researchers used thin crystals of a van der Waals semiconducting transition metal called molybdenum disulfide. Then, they layered six of these crystal pieces into a stack, with each piece rotated 180 degrees relative to the crystal slabs above and below.

Researchers from the Massachusetts Institute of Technology, Purdue University, Stanford University, Rice University, and the U.S. Department of Energy’s Lawrence Berkeley National Laboratory, Argonne National Laboratory, and Oak Ridge National Laboratory have described how a type of quasiparticle, called a polaron, behaves in tellurene, a nanomaterial made up of tiny chains of tellurium atoms. A polaron forms when charge-carrying particles such as electrons interact with vibrations in the atomic or molecular lattice of a material.

Researchers from Case Western Reserve University, the University of Illinois Urbana-Champaign, Adamas Nanotechnologies (Raleigh, NC), the University of Luxembourg in Luxemburg, Umeå University in Sweden, and Aix Marseille University in France have found that boron-doped diamonds exhibit plasmons – waves of electrons that move when light hits them – allowing electric fields to be controlled and enhanced on a nanometer scale. Previously, boron-doped diamonds were known to conduct electricity and become superconductors, but not to have plasmonic properties.

Materials that conduct electricity well, like metals, also tend to conduct heat. But researchers at Drexel University, Villanova University, Temple University, Bryn Mawr College, Rice University, and Université catholique de Louvain in Belgium have discovered that MXenes, a type of material known for its excellent electrical conductivity, actually have very low thermal conductivity. This discovery challenges the usual link between electrical and heat conduction and could lead to new developments in building materials, performance apparel, and energy storage solutions.

Researchers from New York University and Charles University in Prague, Czech Republic, have observed growth-induced self-organized stacking domains when three graphene layers are stacked and twisted with precision. The findings demonstrate how specific stacking arrangements in three-layer graphene systems emerge naturally – eliminating the need for complex, non-scalable techniques traditionally used in graphene twisting fabrication. The size and shape of these stacking domains are influenced by the interplay of strain and the geometry of the three-layer graphene regions.

Scientists at Rice University have made it possible to capture clear images of objects through hot windows. The core of this breakthrough lies in the design of nanoscale resonators, which work like miniature tuning forks trapping and enhancing electromagnetic waves within specific frequencies. The resonators are made from silicon and organized in a precise array that allows fine control over how the window emits and transmits thermal radiation. One immediate application is in chemical processing, in which chemical reactions inside high-temperature chambers need to be monitored.

Researchers from Florida State University; the National High Magnetic Field Laboratory in Tallahassee, FL; and the Universitat de València in Spain have unlocked a new method for producing one class of 2D material and for supercharging its magnetic properties. Experimenting on a metallic magnet made from the elements iron, germanium and tellurium, the research team made two breakthroughs: a collection method that yielded 1,000 times more material than typical practices, and the ability to change the material’s magnetic properties through a chemical treatment.

Researchers from the University of Central Florida have developed a new technique to detect long-wave infrared photons of different wavelengths based on a nanopatterned graphene. "No present cooled or uncooled detectors offer such dynamic spectral tunability and ultrafast response," said Debashis Chanda, the scientist who led this study.

Researchers from the University of Missouri and the U.S. Department of Energy’s Oak Ridge National Laboratory have discovered a new type of quasiparticle that is found in nanostructured magnets, no matter their strength or temperature. "We've all seen the bubbles that form in sparkling water or other carbonated drink products," said Carsten Ullrich, one of the scientists involved in this study.

Researchers at Rice University have found a new way to improve a key element of thermophotovoltaic  systems, which convert heat into electricity via light. Using an unconventional approach inspired by quantum physics, the researchers designed a thermal emitter that can deliver high efficiencies within practical design parameters. The emitter is composed of a tungsten metal sheet, a thin layer of a spacer material and a network of silicon nanocylinders.