Author: sentefmi

Elementary-particle physics in laser-driven materials

Dancing Weyl cones: When excited by tailored laser pulses (white spiral), the cones in a Dirac fermion material dance on a path (8-shape) that can be controlled by the laser light. This turns a Dirac material into a Weyl material, changing the nature of the quasiparticles in it. One of the cones hosts right-handed Weyl fermions; the other cone hosts left-handed ones. [less] © Jörg M. Harms/MPSD
Dancing Weyl cones: When excited by tailored laser pulses (white spiral), the cones in a Dirac fermion material dance on a path (8-shape) that can be controlled by the laser light. This turns a Dirac material into a Weyl material, changing the nature of the quasiparticles in it. One of the cones hosts right-handed Weyl fermions; the other cone hosts left-handed ones. © Jörg M. Harms/MPSD

Our work “Creating stable Floquet-Weyl semimetals by laser-driving of 3D Dirac materials” was published in Nature Communications (doi:10.1038/ncomms13940).

Further reading:
Studying fundamental particles in materials

Understanding the energy flow in a high-temperature superconductor

Microscopic image of one of the bismuth strontium calcium copper oxide samples the scientists studied using a new high-speed imaging technique. Color changes show changes in sample height and curvature to dramatically reveal the layered structure and flatness of the material. Credit: Brookhaven National Laboratory Read more at: http://phys.org/news/2016-12-laser-pulses-scientists-complex-electron.html#jCp
Microscopic image of one of the bismuth strontium calcium copper oxide samples the scientists studied using a new high-speed imaging technique. Color changes show changes in sample height and curvature to dramatically reveal the layered structure and flatness of the material. Credit: Brookhaven National Laboratory

Our work “Energy Dissipation from a Correlated System Driven Out of Equilibrium” was published in Nature Communications (doi:10.1038/ncomms13761).

Further reading:
Laser pulses help scientists tease apart complex electron interactions
Energiefluss im Supraleiter
Laserpulse helfen Forschern, komplexe Elektronenwechselwirkungen zu entflechten

Control of competing orders

In a new theory published on arXiv today we show how a laser beam can exert control in a system with competing superconducting and charge orders. The underlying mechanism with a striking resonance for photon frequencies near the gap edge may even be used to understand light-induced superconductivity. The above figure illustrates how a symmetry between the competing orders allows for low-energy excitations corresponding to a rotation of a composite order parameter towards charge order (CDW, left) or towards superconductivity (SC, right).
Reference: arXiv:1611.04307