Category Archives: Materials

Usually, optical activity is understood as the ability some substances have to change the handedness of polarized light when it goes through them. Molecules that show optical activity have no plane of symmetry. The commonest case of this is in […]

A quantum dot (QD) is a nanometric crystalline structure of semiconductor materials. In a QD electrons are confined in a region of space, thus creating a well defined structure of energy levels that depends very much on the size […]

The interactions between moving charges and magnetic fields can be quite complicated; more if we consider the quantum effects. One example is the collection of Hall effects.
Imagine that we have a conductor or a semiconductor through which a current […]

Proteins can perform a huge number of biological functions with amazing efficiency. In order to achieve these different functions, proteins rely on the precise 3D arrangement of functional groups which are referred to as the protein fold. Some of these […]

Achieving room temperature superconductivity is among the most pursued but elusive goals of scientists. In December 2014 researchers claimed to have observed superconductivity as high as 200 K in hydrogen sulfide at high pressure, breaking all the records thus […]

Plasmonic nanostructures confine light to dimensions far smaller than the free-space wavelength, as they mix optical fields with electronic excitations. It was not until the 1990s, with the appearance of accurate and reliable nanofabrication techniques, that plasmonics blossomed. It […]

Terahertz (THz) radiation is all around us. For example, this page emits blackbody radiation mainly in the THz region (defined here from 0.3 THz to 30 THz). Because terahertz radiation begins at a wavelength of around one millimeter and proceeds […]

Symmetry is a unifying principle that governs all aspects of physics. The physical properties of crystalline solids are no different. But, as symmetry is progressively lowered through the 32 crystallographic point groups, novel transport effects emerge. Crystal symmetry dictates also […]

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. Topological insulators are […]

Nonlinear processes are attractive in microscopy and spectroscopy since they can be excited with light in the near‐infrared, which offers several advantages, from a deep tissue penetration capability or a reduced photodamage due to the lower photon energy, to a […]