Category archives: Theoretical physics

Second-harmonic generation in a quantum emitter – metallic nanoparticle hybrid

Second-harmonic generation in a quantum emitter – metallic nanoparticle hybrid

Condensed matterMaterialsNanotechnologyQuantum physicsTheoretical physics

By DIPC

When two photons with the same energy interact with a nonlinear material, they “combine” and generate a new photon with twice the energy of the initial photons. More precisely, two photons at the fundamental frequency are absorbed by a plasmonic structure to emit one photon at the second-harmonic frequency. This is called second-harmonic generation. Second-harmonic […]

An additional contribution to the spin Hall effect induced by an electric current

An additional contribution to the spin Hall effect induced by an electric current

Condensed matterMaterialsPhysicsTheoretical physics

By DIPC

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 is flowing. Then we apply a strong transverse magnetic field. As a result, we can […]

A local quantum emitter can be used to sense the environment of a molecule with the minimal quantum of energy

A local quantum emitter can be used to sense the environment of a molecule with the minimal quantum of energy

Condensed matterMaterialsNanotechnologyQuantum physicsTheoretical physics

By DIPC

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 was found then that local fields around nanostructures could be directly measured by near-field scanning optical […]

A theory of spin hall magnetoresistance to study magnetism at interfaces

A theory of spin hall magnetoresistance to study magnetism at interfaces

Condensed matterMaterialsQuantum physicsTheoretical physics

By DIPC

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 is flowing. Then we apply a strong transverse magnetic field. As a result, we can […]

Inverse-square law interaction at the nanoscale

Inverse-square law interaction at the nanoscale

Condensed matterQuantum physicsTheoretical physics

By DIPC

Any physical law in which the magnitude of a physical quantity is proportional to the reciprocal of the square of the distance (1/r2) from the source of that property is known as an inverse-square law. Newton’s law of gravitation and Coulomb’s law are both examples. When Newton proposed his law of gravitation in his Philosophiæ […]

The road to quantum gravity (4): The flow of time for massive objects

The road to quantum gravity (4): The flow of time for massive objects

CosmologyHistoryTheoretical physics

By Daniel Fernández

We started this series discussing the basic ingredients of the Universe: events, spacetime, causality. In the last chapter, we introduced massive objects (and thus, matter), which appear as a generalization of the so-called photon box. As it moves, any object traces a path. Physicists call it worldline. We established that a massive object never moves […]

The road to quantum gravity (3): The speed of light and the origin of mass

The road to quantum gravity (3): The speed of light and the origin of mass

CosmologyHistoryTheoretical physics

By Daniel Fernández

In the previous chapter of this series, we went over the subjective, relative separation of the network of events known as Spacetime into space and time. The speed of light played a major role in the discussion. In particular, we divided Spacetime into three regions (with respect to a particular event) defined by the existence […]