As first demonstrated by Tang and Cohen in chiral optics, the asymmetry in the rate of electromagnetic energy absorption between left and right enantiomers is determined by an optical chirality density. Here, we demonstrate that this effect can exist in magnetic spin systems. By constructing a formal analogy with electrodynamics, we show that in antiferromagnets with broken chiral symmetry, the asymmetry in local spin-wave energy absorption is proportional to a spin-wave chirality density, which is a direct counterpart of optical zilch. We propose that injection of a pure spin current into an antiferromagnet may serve as a chiral symmetry breaking mechanism, since its effect in the spin-wave approximation can be expressed in terms of additional Lifshitz invariants. We use linear response theory to show that the spin current induces a nonequilibrium spin-wave chirality density.
Charge current is converted into chiral spin current for energy harvesting.
Quantum Transport Enhancement by Time-Reversal Symmetry Breaking
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The Chiral Anomaly
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Spin resonance was found to occur when the base oscillatory frequency was twice the value of the coupled frequency.
here
Scientists observe gravitational anomaly on Earth
"For the first time, we have experimentally observed this fundamental quantum anomaly on Earth which is extremely important towards our understanding of the universe," said Dr. Johannes Gooth, an IBM Research scientist and lead author of the paper. "We can now build novel solid-state devices based on this anomaly that have never been considered before to potentially circumvent some of the problems inherent in classical electronic devices, such as transistors."
New calculations, using in part the methods of string theory, showed that this gravitational anomaly is also responsible for producing a current if the material is heated up at the same time a magnetic field is applied.
Read more at: https://phys.org/news/2017-07-scientists-gravitational-anomaly-earth_1.html#jCp
"This is an incredibly exciting discovery. We can clearly conclude that the same breaking of symmetry can be observed in any physical system, whether it occurred at the beginning of the universe or is happening today, right here on Earth," said Prof. Dr. Karl Landsteiner, a string theorist at the Instituto de Fisica Teorica UAM/CSIC and co-author of the paper.
IBM scientists predict this discovery will open up a rush of new developments around sensors, switches and thermoelectric coolers or energy-harvesting devices, for improved power consumption.
an underlying curved space-time provides a distinct contribution to a chiral imbalance, an effect known as the mixed axial–gravitational anomaly, but this anomaly has yet to be confirmed experimentally. However, the presence of a mixed gauge–gravitational anomaly has recently been tied to thermoelectrical transport in a magnetic field, even in flat space-time, suggesting that such types of mixed anomaly could be experimentally probed in condensed matter systems known as Weyl semimetals."
the altered electronic response to polarized light allows for the manipulation of the charge order by addressing its chirality.here
3.1. Optical Tweezers and Cold Atom TrappingThe interaction of light with helicoid wavefronts with a microscopic dielectric particleresults in a transfer of angular momentum to the particle. This causes particle to rotatearound the beam axis[5]. The optical tweezers use the gradient force that is due to thetightly focused beam of light to trap dielectric particles. The modes with well definedOAM can be used in optical tweezers, and creating optically driven micromachines, sincethe rotation of the particles acts as a microfluidic pump[12].
Orbital Angular Momentum of Light (PDF Download Available). Available from: https://www.researchgate.net/
Pinning of longitudinal phonons in holographic helical crystals - arXiv
Black hole elasticity and gapped transverse phonons in holography
of holographic models with broken translational invariance. We compute the transverse
quasi-normal mode spectrum and determine the propagation speed of the lowest energy
Spintronics
Molecular spintronics (spin + electronics), which aims to exploit both the spin degree of freedom and the electron charge in molecular devices, has recently received massive attention. Our recent experiments on molecular spintronics employ chiral molecules which have the unexpected property of acting as spin filters, by way of an effect we call “chiral-induced spin selectivity” (CISS).
Chiral Induced Spin Selectivity (CISS).(4, 5) The studies described here use a chiral linker molecule between the redox moiety and a ferromagnetic electrode to provide a spin filter for the electrons, via the CISS effect, and they combine it with an externally applied static magnetic field that switches the direction of magnetization of the ferromagnetic electrode to unveil the spin selectivity in the electron transfer process.
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