#1d materials

A bizarre new state of matter may be hiding inside Uranus and Neptune

The deep interiors of ice giant planets such as Uranus and Neptune may contain a previously unknown form of matter. This possibility comes from new computer simulations conducted by Carnegie scientists Cong Liu and Ronald Cohen. Their study, published in Nature Communications, suggests that carbon hydride could take on an unusual quasi-one-dimensional superionic state under the intense pressures and temperatures found far beneath the surfaces of these distant planets.

Scientists confirm one-dimensional electron behavior in phosphorus chains

Atom-thin phosphorus chains have been shown to host true 1D electrons—and squeezing them tighter could turn them metallic.

Researchers at BESSY II have, for the first time, experimentally confirmed that a material can exhibit truly one-dimensional electronic properties. The team studied short chains of phosphorus atoms that naturally arrange themselves at specific angles on a silver surface. By applying advanced measurement and analysis techniques, they separated the signals coming from chains aligned in different directions. This careful work showed that each individual chain behaves as a genuine one-dimensional electronic system. The findings also point to a dramatic shift in behavior depending on how closely the chains are spaced. When the chains are farther apart, the material acts as a semiconductor. If packed tightly together, however, calculations predict it would behave like a metal.

One tiny diode could shrink image sensors by adding memory and processing

P-n diodes are two-terminal devices that consist of two types of semiconductor materials (i.e., a p-type and an n-type material) joined together. These components allow electric current to only move in one direction, which is central to the functioning of many electronic circuits. Conventional p-n diodes only perform a single function, namely that of enabling the flow of current in one direction. This means that other components are required to also perform computations, store data or detect specific signals. Researchers at University of Science and Technology of China and McGill University in Canada recently designed a new p-n diode that can perform three different functions without the need to be integrated with additional components. Their device, presented in a paper published in Nature Electronics, is based on one-dimensional (1D), gallium nitride (GaN) and aluminum gallium nitride (AlGAN)-based structures known as nanowires.

Phosphorus chains display true 1D electronic properties on a silver substrate

For the first time, a team at BESSY II has succeeded in demonstrating the one-dimensional electronic properties of a material through a highly refined experimental process. The samples consisted of short chains of phosphorus atoms that self-organize at specific angles on a silver substrate. Through sophisticated analysis, the team was able to disentangle the contributions of these differently aligned chains. This revealed that the electronic properties of each chain are indeed one-dimensional. Calculations predict an exciting phase transition to be expected as soon as these chains are more closely packed. While material consisting of individual chains with longer distances is semiconducting, a very dense chain structure would be metallic. The work is published in the journal Small Structures.

Silicon nanowires self-assemble into macroscopic networks for advanced materials

Researchers at IMDEA Materials Institute have developed a pioneering method to assemble silicon nanowires into ordered, macroscopic networks: a key step toward expanding their industrial applications. Silicon nanowires offer exceptional energy storage capacity, electrical conductivity, and mechanical strength, making them ideal for next-generation batteries, electronics, and advanced functional materials. However, individual silicon nanowires are just 10–50 nanometers in diameter, roughly 1,000 times thinner than a strand of human hair. As such, many of their most promising current and potential applications require the ability to process and assemble them into larger bundles.

A chain of copper and carbon atoms may be the thinnest metallic wire

Researchers from the Laboratory for Theory and Simulation of Materials at EPFL in Lausanne, part of the NCCR MARVEL, have used computational methods to identify what could be the thinnest possible metallic wire, as well as several other unidimensional materials with properties that could prove interesting for many applications. Unidimensional (or 1-D) materials are one of the most intriguing products of nanotechnology and are made of atoms aligned in the form of wires or tubes. Their electrical, magnetic, and optical properties make them excellent candidates for applications ranging from microelectronics to biosensors to catalysis. While carbon nanotubes are the materials that have received most of the attention so far, they have proved very difficult to manufacture and control, so scientists are eager to find other compounds that could be used to create nanowires and nanotubes with equally interesting properties, but easier to handle.

Scientists trap krypton atoms to form one-dimensional gas

For the first time, scientists have successfully trapped atoms of krypton (Kr), a noble gas, inside a carbon nanotube to form a one-dimensional gas. Scientists from the University of Nottingham's School of Chemistry used advanced transmission electron microscopy (TEM) methods to capture the moment when Kr atoms joined together, one by one, inside a "nano test tube" container with diameter half a million times smaller than the width of a human hair. The research has been published in ACS Nano. The behavior of atoms has been studied by scientists ever since it was hypothesized that they are the basic units of the universe. The movement of atoms has significant impact on fundamental phenomena such as temperature, pressure, fluid flow and chemical reactions. Traditional spectroscopy methods can analyze the movement of large groups of atoms and then use averaged data to explain phenomena at the atomic scale. However, these methods don't show what individual atoms are doing at a specific point in time.

A research team led by Director JO Moon-Ho of the Center for Van der Waals Quantum Solids within the Institute for Basic Science (IBS) has implemented a novel method to achieve epitaxial growth of 1D metallic materials with a width of less than 1 nm. The group applied this process to develop a new structure for 2D semiconductor logic circuits. Notably, they used the 1D metals as a gate electrode of the ultra-miniaturized transistor. Integrated devices based on two-dimensional (2D) semiconductors, which exhibit excellent properties even at the ultimate limit of material thickness down to the atomic scale, are a major focus of basic and applied research worldwide. However, realizing such ultra-miniaturized transistor devices that can control the electron movement within a few nanometers, let alone developing the manufacturing process for these integrated circuits, has been met with significant technical challenges.