Researchers have developed methods to explore and utilize superconductivity in non-equilibrium states, such as those induced by laser pulses, at temperatures much higher than traditional superconductors operate.
This light-induced superconductivity has been shown to replicate crucial features like zero electrical resistance and expulsion of magnetic fields, suggesting potential applications in high-speed devices and extending superconductivity to ambient temperatures.
Superconductors are remarkable materials that can carry an electrical current with zero loss. This collective quantum behavior is unique to certain conductors and only occurs at temperatures significantly below room level.
A number of modern studies have investigated this behavior in non-equilibrium states, which are situations where the material is pushed away from thermal equilibrium. In these conditions, it appears that at least some features of superconductivity can be recreated even at ambient temperatures.
The phenomenon has been termed “light-induced superconductivity,” signaling an analogy with its equilibrium counterpart.
An important frontier in recent years has been to characterize the properties of one such light-induced superconducting state and understand how far this phase reproduces the known properties of a conventional superconductor.
Besides being capable of transporting electrical currents without loss, superconductors are also known to expel magnetic fields from their interior. This phenomenon is a direct consequence of the mutual coherence of the charge carriers and their tendency to march in lockstep.
A team of researchers at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) has developed a new experiment capable of monitoring the magnetic properties of superconductors at very fast speeds.
The researchers have discovered that photo-excited YBa2Cu3O6.48, in addition to featuring near zero resistance, also expels a static magnetic field from its interior.
This experiment was made possible by placing a spectator crystal in close vicinity of the sample under investigation and using it to measure the local magnetic field strength.
The results suggest that photo-excitation of YBa2Cu3O6.48 with tailored light pulses can be used to synchronize this flucting state and restore the superconducting order at temperatures much higher than the ones at which the material becomes superconducting.
Reference: “Magnetic field expulsion” by S. Fava, G. De Vechi, M. Buzzi, T. Gebert, Y Liu, Keimer and A. Cavalleri, 10 July 20, Nature DOI: 10.38/s41586-0247s/50.38/DOI: 10.38/s41586-24; DOI: 10.38/s41586-24; DOI: 10.38;s/15.36; DOI: 10.38;s/15.36; DOI: 10.38;s/15.36; DOI: 10.38;s/15.36; DOI: 10.38;s/15.36;
Source: https://scitechdaily.com/light-induced-superconductivity-a-new-frontier-in-quantum-physics/