One of the most mysterious features of quantum mechanics is that if two particles (or photons) interact at some point in time then the properties of these particles will remain connected at future times. A consequence of this is that determining the quantum state of one of the particles simultaneously determines the quantum state of […]
Condensed matter • Materials • Nanotechnology • Quantum physics • Theoretical physics
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 […]
Condensed matter • Materials • Nanotechnology • Quantum physics • Theoretical physics
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 […]
Chemistry • Condensed matter • Materials • Nanotechnology • Quantum physics
A quantum dot is a nanometric crystalline structure of semiconductor materials. In a quatum dot electrons are confined in a region of space, thus creating a well defined structure of energy levels that depends very much on the size and shape of the quantum dot. This structure resembles that of atoms, that is why sometimes […]
The ability to trap and control particles with the help of well-controlled electromagnetic fields has led to revolutionary advances in the fields of biology, condensed- matter physics, high-precision spectroscopy, and quantum information, enabling unprecedented control both in the study of isolated single particles as well as in few and many-body systems subject to controlled and […]
Particle physics is an interesting and complicated field of study. Its theoretical framework, the Standard Model, was developed during the second half of the twentieth century and it opened he possibility to explaining the behavior of the basic blocks of the Universe. It also classified all the particles, from the electron (discovered in 1897) to […]
At a fundamental level the term “quantum computing” implies de use of quantum effects that have no classical analogue to process information. In a “classical computer” information is held in bits, which can have two alternative values (0 and 1). quantum computer the values 0 and 1 are held simultaneously in an entangled state. This […]
Sunlight is the most important energy source of Earth. All earthlings live thanks to the ability of plants and bacteria to transform solar energy into chemical one. As sunlight is a free, and practically unlimited, energy source it is easy to understand the general interest in finding efficient ways of transforming it into electrical power […]
Quantum computers are one of the most promising technologies under development, and all their promises are completely justified. Quantum systems are extremely expensive to compute, where “expensiveness” can be measured either by the memory or the computational time required in classical computers. But it should be much cheaper if the computer uses quantum mechanics rules […]
An international research team has presented a new quantum platform based on the electron spin of single atoms on a solid surface, achieving a ‘multiple qubit (quantum bit)’ system using three electron spins. Unlike previous atomic quantum devices on surfaces where only a single qubit could be controlled, the researchers have successfully demonstrated the ability […]