Observation of Resonant Quantum Magnetoelectric Effect in a Multiferroic Metal–Organic Framework

A resonant quantum magnetoelectric
coupling effect has been demonstrated
in the multiferroic metal–organic framework of [(CH3)2NH2]­Fe­(HCOO)3. This material shows
a coexistence of a spin-canted antiferromagnetic order and ferroelectricity
as well as clear magnetoelectric coupling below TN ≈ 19 K. In addition, a component of single-ion
quantum magnets develops below ∼8 K because of an intrinsic
magnetic phase separation. The stair-shaped magnetic hysteresis loop
at 2 K signals resonant quantum tunneling of magnetization. Meanwhile,
the magnetic field dependence of dielectric permittivity exhibits
sharp peaks just at the critical tunneling fields, evidencing the
occurrence of resonant quantum magnetoelectric coupling effect. This
resonant effect enables a simple electrical detection of quantum tunneling
of magnetization.