Qiang Li – October 21, 2016

Chiral Magnetic Effect in Condensed Matters

Qiang Li, Brookhaven National Labratory
PSB 160/161, 4:00-5:00pm

 Abstract: The chiral magnetic effect is the generation of electrical current induced by chirality imbalance in the presence of magnetic field. It is a macroscopic manifestation of the quantum chiral anomaly in systems possessing charged chiral fermions. In quark-gluon plasma containing nearly massless quarks, the chirality imbalance is sourced by the topological transitions. In condensed matter systems, the chiral quasiparticles emerge in the Dirac and Weyl semimetals having a linear dispersion relation. Recently, the chiral magnetic effect was discovered first in a 3D Dirac semimetal ZrTe5, in which we observed a large negative magnetoresistance when magnetic field is parallel with the current. The measured quadratic field dependence of the magnetoconductance is a clear indication of the chiral magnetic effect [Li et al arXiv:1412.6543, Nature Physics (2016) doi:10.1038/nphys3648)]. It is now observed in more than half a dozen Dirac and Weyl semimetals. 3D Dirac/Weyl semimetals have opened a fascinating possibility to study the quantum dynamics of relativistic field theory in condensed matter experiments, with potential for important practical applications.