Category archives: Nanotechnology

The so-called van der Waals materials consist of two-dimensional layers bound by weak van der Waals forces. After the isolation of graphene, the field of two-dimensional van der Waals materials has experienced an explosive growth and new families of two-dimensional systems and block-layered bulk materials have been created. This growth has been fueled mainly by […]

For centuries, metals were employed in optical applications only as mirrors and gratings. New vistas opened up in the late 1970s and early 1980s with the discovery of surface-enhanced Raman scattering (SERS) and the use of surface plasmon (collective electronic oscillations at the surface of metals) resonances for sensing. In a simplified picture and in […]

If a nucleus has a nonzero spin, it behaves as a small magnet. Therefore, in an external magnetic field, the nuclear magnetic moment vector precesses about the field direction but only certain otientations are allowed by quantum rules. Thus, for hydrogen (spin 1/2) there are two possible states in the presence of a field, each […]

So-called “valleytronics” is a new type of electronics that could lead to faster and more efficient computer logic systems and data storage chips in next-generation devices. Valley electrons are so named because they carry a valley degree of freedom, a pseudospin. This is a new way to harness electrons for information processing that’s in addition […]

In 1873, the microscopist Ernst Abbe stipulated a physical limit for the maximum resolution of traditional optical microscopy: 0.2 micrometers, or 200 nanometers (the shortest wavelength for visible light, the extreme limit of violet). This meant that scientists could distinguish whole cells, as well as some parts of the cell called organelles. However, they would […]

A region containing a maximum of potential that prevents a particle on one side of it from passing to the other side is called a potential barrier. The net in a tennis court is in a certain way a potential barrier, as the ball needs to have kinetic energy in excess of the height of […]

Controlling electron waves by harnessing phase-coherence and interference effects is a cornerstone for future nanoelectronics or quantum computing. To this end, design of platforms with well-defined, narrow, and low-loss propagation channels is essential. Nanoporous graphene (NPG) holds great potential for distributing and controlling currents on the nanoscale. But the effects derived from the wave nature […]

Every year the amount of data produced is of the order of magnitude of the Avogadro’s constant, thus 6.028×1023. This trend is supposed to increase even more in the next future. This implies that more and more special metals will be needed. The point is: what might happen if the resources used for manufacturing common […]

Light waves spread and bend as they pass through an aperture or round the edge of a barrier. This is a well-known phenomenon called diffraction. Diffraction imposes a limit to the size of objects that we can observe sharply using light of a given wavelength, for a given microscope will have a minimum aperture, and […]

You can read this article because I have used photonics in order to make it possible. It may sound futuristic, but photonics is a technology we use, one way or the other, on a daily basis. Photonic devices are analogous to those used in electronics, but with the electrons replaced by photons. Thus, photonics is […]