Individual domain characteristics determined by second-harmonic generation diffractometer for multi-domain multiferroics.

We investigated the multi-domain states of a multiferroic La-doped BiFeO (BLFO) thin film by examining diffraction patterns in optical second-harmonic generation (SHG) measurement. By directing a laser onto the domain wall within the domain-patterned sample, we observed clear diffraction signatures of SHG waves generated from two ferroelectric domains. We explained the experimental results of the diffraction patterns, including the intensity distribution and the polarization characteristics, using Fresnel propagation of SHG waves.

Broken Inversion Symmetry in Van Der Waals Topological Ferromagnetic Metal Iron Germanium Telluride.

Inversion symmetry breaking is critical for many quantum effects and fundamental for spin-orbit torque, which is crucial for next-generation spintronics. Recently, a novel type of gigantic intrinsic spin-orbit torque is established in the topological van der Waals (vdW) magnet iron germanium telluride. However, it remains a puzzle because no clear evidence exists for interlayer inversion symmetry breaking.

Multiferroic-Enabled Magnetic-Excitons in 2D Quantum-Entangled Van der Waals Antiferromagnet NiI.

Matter-light interaction is at the center of diverse research fields from quantum optics to condensed matter physics, opening new fields like laser physics. A magnetic exciton is one such rare example found in magnetic insulators. However, it is relatively rare to observe that external variables control matter-light interaction.

Possible Persistence of Multiferroic Order down to Bilayer Limit of van der Waals Material NiI.

Realizing a state of matter in two dimensions has repeatedly proven a novel route of discovering new physical phenomena. Van der Waals (vdW) materials have been at the center of these now extensive research activities. They offer a natural way of producing a monolayer of matter simply by mechanical exfoliation.