When these circuits are built of superconductor materials and at near-absolute zero cryogenic temperatures, the world of everyday physics is left behind and the amazing world of quantum physics is entered. In this circuit the behaviour is something like an artificial atom (i.e. like the so-called quantum bits (“qubits”) of quantum computers) and the concepts of quantum optics, quantum information and condensed matter are mixed.
An Ikerbasque researcher, ascribed to the University of the Basque Country (UPV/EHU), Enrique Solano, together with colleagues from Germany and Japan, have been working on an experiment and a theoretical model that show that certain quantum leaps are prohibited at times between levels of a qubit superconductor. This phenomenon is produced on sending photons of light with sufficient energy against a qubit installed within a circuit that simulates the behaviour of microwaves, similar to the ovens commonly used domestically but at a micrometric scale. The research has been published in the prestigious Nature Physics journal under the title, ‘Two-photon probe of the Jaynes-Cummings model and Controlled Symmetry Breaking in Circuit QED’. The article may be consulted on-line and will be included in the next print issue of the journal.
To explain this in an easy way, let us go back to our household circuit where, as with any such circuit, sufficient energy has to be supplied in order to move electrons from one place to another, i.e. the required voltage has to be applied. In an atomic circuit, however, the required energy is supplied through photons of light but this is not sufficient to produce the famous quantum jumps between two atomic energy levels. The additional required factor is the presence of the symmetry of the qubit, an enhancing factor, as it were.
It is as if it were not enough for the quantum nature to have the required energy and it requires, moreover, the presence of the qubit to enable – or otherwise – the quantum leaps stimulated by the photons of light energy. If the qubit presents itself with symmetrical potential, the jump is prohibited and is not produced; curiously, if the potential is asymmetric, the quantum leap is permitted. This strange behaviour has been demonstrated by these researchers both at a theoretical level and in the laboratory, where the rules of prohibition may be activated and deactivated at will.
This research is an important step in the thorough understanding of the quantum jumps permitted and prohibited in superconductor circuits, as well as in the potential application of the electrodynamic quantum of circuits to future technology in quantum computation and information.
Enrique Solano is a PhD in Physics from the Federal University of Río de Janeiro. After working at the Ludwig-Maximilian University in Munich, he has been carrying out his research over the last few months at the UPV/EHU thanks to an agreement between the University and the Ikerbasque Foundation.
Garazi Andonegi | alfa
SF State astronomer searches for signs of life on Wolf 1061 exoplanet
20.01.2017 | San Francisco State University
Molecule flash mob
19.01.2017 | Technische Universität Wien
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences