http://arxiv.org/pdf/1412.6543.pdf
The chiral magnetic effect is the generation of electric current induced by chirality imbalance in the presence of magnetic field. It is a macroscopic manifestation of the quantum anomaly1,2 in relativistic field theory of chiral fermions (massless spin 1/2 particles with a definite projection of spin on momentum) – a dramatic phenomenon arising from a collective motion of particles and antiparticles in the Dirac sea. The recent discovery3–5 of Dirac semimetals with chiral quasi-particles opens a fascinating possibility to study this phenomenon in condensed matter experiments. Here we report on the first observation of chiral magnetic effect through the measurement of magneto-transport in* zirconium pentatelluride, ZrTe5*. Our angle-resolved photoemission spectroscopy experiments show that this material’s electronic structure is consistent with a 3D Dirac semimetal. We observe 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. The observed phenomenon stems from the effective transmutation of *Dirac semimetal into a Weyl semimetal* induced by the parallel electric and magnetic fields that represent a topologically nontrivial gauge field background. I had it backward, the magnetic field produces Weyl quasiparticles, On Mon, Aug 29, 2016 at 9:26 PM, John Berry <[email protected]> wrote: > "zirconium pentatelluride,ZrTe5, that provides strong evidence for the > chiral magnetic effect:. > > My research is all based on chirality of coils that produce fundamentally > different "currents". > > This is no doubt closely related to my work! > > On Tue, Aug 30, 2016 at 1:23 PM, John Berry <[email protected]> > wrote: > >> "This is because in ZrTe5 the electrons responsible for the current have >> no mass." >> >> That itself sounds like a dramatic claim, electrons with no mass? >> >> I am able to produce a current of something that I believe is like an >> electron albeit not propperly physical, and I believe it gains something by >> moving through magnetic fields. >> >> I think I might be moving something akin to a virtual electron, albeit >> one that does not have the correct quanta to manifest physically to regular >> meters, but can be readily detected by a significant percentage of the >> population including in conditions outside of any possible >> conventional explanation like the Placebo effect. >> >> But there is another current in the reverse direction that is denser and >> appears to be more like a proton. >> >> John >> >> On Tue, Aug 30, 2016 at 11:58 AM, Jack Cole <[email protected]> wrote: >> >>> Electrons with no mass acquire a mass in the presence of a high magnetic >>> field >>> >>> http://flip.it/bkDC21 >>> >> >> >
