Scientists seeking better methods for controlling the quantum interactions between light and matter demonstrated a novel way to use light to give electrons a spinning kick. The results of their experiment show that a light beam can reliably transfer orbital angular momentum to itinerant electrons in graphene. Having tight control over the way that light […]
In certain materials, when we apply an electric field (it could be that of light) that vibrates at a certain frequency, it can create a direct current, a steady flow of electrical charge. This current is special because its strength depends on the square of the electric field’s strength. This phenomenon is called “shift current.” […]
A gauge theory is any number of quantum field theories put forward to explain fundamental interactions. In these theories the interactions between particles can be explained by the exchange of particles such as gluons, photons, and W and Z bosons. A gauge theory involves a symmetry group for the fields and potentials (the gauge group) […]
Topological insulators are materials with special universal properties, which are protected against perturbations. Such properties are theoretically described by topology, a branch of mathematics concerned with the properties of geometrical objects that are unchanged by continuous deformations. Concretely, topological insulators are electronic materials that have a bulk band gap like an ordinary insulator but have […]
A diode is an electronic device with two electrodes. In the obsolescent thermionic diode a heated cathode emits electrons, which flow across the intervening vacuum to the anode when a positive potential is applied to it. The device permits flow of current in one direction only as a negative potential applied to the anode repels […]
Liquid crystals are all around us, from cell phone screens and video game consoles to car dashboards and medical devices. Run an electric current through liquid crystal displays (LCDs) and they generate colours, thanks to the unique properties of these fluids: rearrange their shape, and they reflect different wavelengths of light. As the lab of […]
Author: Leah Burrows, Harvard John A. Paulson School of Engineering and Applied Sciences The earliest blacksmiths in the Bronze and Iron Ages figured out that when they deformed metal through bending or hammering, it became stronger. This process, known as work or strain hardening, is still used widely in metallurgy and manufacturing today to increase […]
Condensed matter • DIPC Interfaces • Materials • Nanotechnology • Quantum physics
Molecular spintronics is an emerging field that combines ferromagnetic materials with organic or metal–organic semiconductors. It benefits from the unique and exceptional properties of organic molecules, which go beyond inorganic ones. The strong response of many organic molecules to electrical, optical, ferromagnetic or antiferromagnetic stimuli bring new potential functionalities to the spintronic device. An effective […]
Condensed matter • DIPC Advanced materials • Quantum physics
The discovery of materials with topologically nontrivial electronic bands has led to high-throughput computational efforts that uncovered such bands in most known inorganic crystalline materials. Thus, in 2017, a team of researchers presented what they called Topological Quantum Chemistry (TQC), a new and complete understanding of the structure of bands in a material that links […]
In the era of big data, signal processing faces significant challenges in terms of capacity and energy consumption due to the torrent of data to process. With over 90% of data transmitted through light, optical signal processing may offer unprecedented speed and energy efficiency compared to its electronic counterparts, as it operates without the need […]