Browsing by Author "Pu, Shi"

Now showing 1 - 2 of 2

Chiral Hall effect and chiral electric waves
(2015-01-14)
Pu, Shi
;
Wu, Shang-Yu
;
Yang, Di-Lun
;
物理研究所
;
丘成桐中心
We investigate the vector and axial currents induced by external electromagnetic fields and chemical potentials in chiral systems at finite temperature. Similar to the normal Hall effect, we find that an axial Hall current is generated in the presence of the electromagnetic fields along with an axial chemical potential, which may be dubbed as the "chiral Hall effect" (CHE). The CHE is related to the interactions of chiral fermions and exists with a nonzero axial chemical potential. We argue that the CHE could lead to nontrivial charge distributions at different rapidity in asymmetric heavy ion collisions. Moreover, we study the chiral electric waves led by the fluctuations of the vector and axial chemical potentials along with the chiral electric separation effect, where a density wave propagates along the applied electric field. Combining with the normal/chiral Hall effects, the fluctuations of chemical potentials thus result in Hall density waves. The Hall density waves may survive even at zero chemical potentials and become nondissipative. We further study the transport coefficients including the Hall conductivities, damping times, wave velocities, and diffusion constants of chiral electric waves in a strongly coupled plasma via the AdS/CFT correspondence.
Holographic chiral electric separation effect
(2014-04-10)
Pu, Shi
;
Wu, Shang-Yu
;
Yang, Di-Lun
;
物理研究所
;
丘成桐中心
We investigate the chiral electric separation effect, where an axial current is induced by an electric field in the presence of both vector and axial chemical potentials, in a strongly coupled plasma via the Sakai-Sugimoto model with a U(1)(R) x U(1)(L) symmetry. By introducing different chemical potentials in U(1)(R) and U(1)(L) sectors, we compute the axial direct current (DC) conductivity stemming from the chiral current and the normal DC conductivity. We find that the axial conductivity is approximately proportional to the product of the axial and vector chemical potentials for arbitrary magnitudes of the chemical potentials. We also evaluate the axial alternating current (AC) conductivity induced by a frequency-dependent electric field, where the oscillatory behavior with respect to the frequency is observed.