Polyanisotropic Magnetoelectric Coupling in an Electrically Controlled Molecular Spin Qubit.

Area of Science:

• Molecular magnetism
• Quantum information science
• Materials science

Background:

• Molecular spin qubits are promising for quantum technologies.
• Understanding magnetoelectric (ME) couplings is crucial for electric spin control.
• Dzyaloshinskii-Moriya interactions (DMI) influence magnetic anisotropy.

Purpose of the Study:

• To investigate magnetoelectric (ME) couplings and electric spin control in two molecular spin qubits.
• To correlate ME effects with molecular structure and Dzyaloshinskii-Moriya interactions (DMI).
• To explore the dependence of ME effects on electric field orientation and magnetic field alignment.

Main Methods:

• Pulsed electron paramagnetic resonance (EPR) spectroscopy under electric fields.
• Characterization of [Fe3O(PhCOO)6(py)3]ClO4·py (Fe) and [Cr3O(PhCOO)6(py)3]ClO4·0.5py (Cr) molecular spin qubits.
• Analysis of magnetoelectric (ME) couplings and electroanisotropy.

Main Results:

• The Fe molecule demonstrated a clear ME effect with orientation-dependent intensity (electroanisotropy and magnetoelectric anisotropy).
• Coherent electric spin control was observed in the Fe molecule, with complex dynamics including saturation and oscillations.
• The Cr molecule, with negligible DMI, showed no discernible ME effect.

Conclusions:

• Strong Dzyaloshinskii-Moriya interactions (DMI) in the Fe molecule are key to its significant magnetoelectric (ME) effect and electric spin control.
• The absence of a discernible ME effect in the Cr molecule correlates with its weak DMI.
• Molecular design and orientation are critical for achieving efficient electric control of spin qubits.