Abstract
We model the magnetic ratchet effect in bilayer graphene in which a dc electric current is produced by an ac electric field of frequency in the presence of a steady in-plane magnetic field and inversion-symmetry breaking. In bilayer graphene, the ratchet effect is tunable by an external metallic gate which breaks inversion symmetry. For zero in-plane magnetic field, we show that trigonal warping and inversion-symmetry breaking are able to produce a large dc valley current, but not a nonzero total dc charge current. For the magnetic ratchet in a tilted magnetic field, the perpendicular field component induces cyclotron motion with frequency and we find that the dc current displays cyclotron resonance at , although this peak in the current is actually smaller than its value at . Second harmonic generation, however, is greatly enhanced by resonances at and for which the current is generally much larger than at .
- Received 15 November 2017
DOI:https://doi.org/10.1103/PhysRevB.97.075415
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