Chirality-Induced Spin Selectivity (CISS) Effect: Magnetocurrent-Voltage Characteristics with Coulomb Interactions I

Area of Science:

• Condensed Matter Physics
• Molecular Electronics
• Quantum Chemistry

Background:

• Chirality-induced spin selectivity (CISS) is a phenomenon where chiral molecules can induce spin polarization in charge currents.
• Magnetocurrent, a change in current due to magnetization, is a key manifestation of CISS.
• Existing theories predict an even bias voltage dependence for magnetocurrent, contrasting with experimental findings.

Purpose of the Study:

• To investigate the bias voltage dependence of magnetocurrent in chiral molecular systems.
• To reconcile theoretical predictions with experimental observations of magnetocurrent symmetry.
• To explore the role of Coulomb interactions in CISS phenomena.

Main Methods:

• Numerical and analytical analysis of magnetocurrent.
• Inclusion of spin-orbit and Coulomb interactions.
• Application of Hartree-Fock and Hubbard One approximations.

Main Results:

• For strong Coulomb interactions, the magnetocurrent exhibits a dominantly odd bias voltage dependence.
• Both Hartree-Fock and Hubbard One approximations support the odd bias voltage dependence under strong Coulomb interactions.
• The theoretical findings align with experimental observations of magnetocurrent symmetry.

Conclusions:

• Strong Coulomb interactions are crucial for observing an odd bias voltage dependence in magnetocurrent.
• This study provides a theoretical framework that explains the experimental magnetocurrent symmetry in chiral molecular systems.
• The findings advance the understanding of spin-dependent transport phenomena in molecular spintronics.