Abstract
It was recently shown that a finite imbalance between electron densities in the K and K′ valleys of bilayer graphene induces a magnetoelectric coupling. Here we explore ramifications of this electronically tunable magnetoelectric effect for the optical conductivity and dielectric permittivity of this material. Our results augment current understanding of longitudinal magnetoresistance and magnetocapacitance in unconventional materials.
Highlights
The coupling of electric and magnetic degrees of freedom in materials continues to be studied intensely, because of both its interesting physical origin and its potential for useful applications [1,2,3,4,5]
We summarize the basic constitutive relations that represent the chiral magnetic effect [10,11,12,13,14,15,16] in Dirac and Weyl semimetals with two valleys characterized by opposite chirality
Our study has revealed the existence of a longitudinal magnetoconductivity and an associated magnetocapacitance in bilayer graphene (BLG) arising from its valley-density-dependent magnetoelectric effect
Summary
The coupling of electric and magnetic degrees of freedom in materials continues to be studied intensely, because of both its interesting physical origin and its potential for useful applications [1,2,3,4,5]. Due to its asymmetric coupling to the K and K′ valleys, simultaneous application of electric and magnetic fields gives rise to a valley-charge imbalancev ≡ ̺K − ̺K′ = 2e2 ξ D(EF) B · E. This represents an intriguing analogy with the situation in the Dirac or Weyl semimetals, see Eq (1) above. While there is some similarity between (6) and the constitutive relation (2) for the Weyl semimetals, there is the crucial difference that the current arising from magnetoelectric coupling in BLG is not proportional tov itself but to its time derivative
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
