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arXiv · 2401.11222

Electric-field-enhanced second-harmonic domain contrast and nonreciprocity in a van der Waals antiferromagnet

Ziqian Wang·Meng Wang·Jannis Lehmann·Yuki Shiomi·Taka-hisa Arima·Naoto Nagaosa·Yoshinori Tokura·Naoki Ogawa
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Abstract

Imaging antiferromagnetic 180{\deg} domains with actively controlled visibility is vital for both fundamental science and sophisticated applications. While optical second-harmonic generation (SHG) is a well-known technique for distinguishing such domains in non-centrosymmetric antiferromagnets, a general material-based strategy to control domain contrast remains elusive. Using van der Waals antiferromagnet MnPS$_3$ as a proof of concept, we demonstrate the tuning of nonreciprocity-induced domain contrast in SHG through applying an in-plane electric field that transforms the magnetic point group to its unitary subgroup. The interference among intrinsic electric-dipole, magnetic-dipole, and field-induced electric-dipole transitions, each carrying distinct characters under space-inversion ($\mathcal{P}$) and time-reversal ($\mathcal{T}$) operations, enables large tuning of domain contrast and nonreciprocity in a broad spectral range. This strategy, generically applicable to systems characterized by $\mathcal{PT}$-symmetric magnetic groups with a polar unitary subgroup, offers a path to fast electrical modulation of nonlinear nonreciprocal photonic behaviors using antiferromagnets.

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Ziqian Wang, Meng Wang, Jannis Lehmann, Yuki Shiomi, Taka-hisa Arima, Naoto Nagaosa, Yoshinori Tokura, Naoki Ogawa. 2024-01-20. Electric-field-enhanced second-harmonic domain contrast and nonreciprocity in a van der Waals antiferromagnet. https://doi.org/10.1038/s41467-024-51943-0

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