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Related Experiment Video

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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser

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Published on: June 28, 2018

Spin-polarized quantum pumping in bilayer graphene.

Jun-Feng Liu¹, K S Chan

¹Department of Physics and Materials Science, City University of Hong Kong, Kowloon, Hong Kong, People's Republic of China. junfeliu@cityu.edu.hk

|September 6, 2011

Summary

We explored adiabatic quantum pumping in bilayer graphene, finding quasiparticle chirality significantly impacts pumped current. Introducing ferromagnetic proximity enables tunable spin-polarized currents for spintronics.

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Area of Science:

Condensed Matter Physics
Quantum Optics
Materials Science

Background:

Adiabatic quantum pumping is a method to drive currents in quantum systems.
Bilayer graphene exhibits unique electronic properties due to its band structure.
Chirality plays a crucial role in the transport properties of Dirac and Weyl fermions.

Purpose of the Study:

To investigate adiabatic quantum pumping in bilayer graphene.
To understand the influence of quasiparticle chirality on pumped currents.
To explore the generation of spin-polarized currents using ferromagnetic proximity.

Main Methods:

Theoretical study of adiabatic quantum pumping in bilayer graphene.
Analysis of quasiparticle transport through modulated two-barrier potentials.
Inclusion of exchange splitting from ferromagnetic insulators to induce spin polarization.

Main Results:

Quasiparticle chirality in bilayer graphene significantly affects pumped current via chiral tunneling.
Exchange splitting leads to spin-polarized pumped currents.
Achieved conditions for nearly 100% polarized charge current and pure spin currents.

Conclusions:

Bilayer graphene is a promising platform for spintronics applications.
Quantum pumping in bilayer graphene offers tunable control over charge and spin currents.
Experimental feasibility and interlayer asymmetry effects are crucial for device realization.