Tailoring Photoinduced Nonequilibrium Magnetizations in In₂Se₃ Bilayers

Magnetization generation and accumulation in intrinsically nonmagnetic materials is one of the key routes to various exotic applications, especially realizing fast information storage and memory devices. Among the various approaches for magnetization injection, light irradiation is advantageous for its noncontacting and non-invasive nature, and has been receiving great attention during the past few decades. In the current work, a quadratic response theory and first-principles calculations are applied to reveal photoinduced magnetization in recently discovered 2D In₂Se₃ bilayers. The ferroelectric In₂Se₃ bilayers can be (meta-) stabilized in versatile stacking patterns, exhibiting largely tunable electronic band structure, and optical feature. Hence, it is suggested that under circularly polarized light illumination, the system can show different photoinduced magnetization responses with large contrast in different stacking patterns. The magnetizations are composed by both spin and orbital angular momentum contributions, which can reach as large as 1μ_B under a laser with intermediate intensity (≈10⁹ W cm^–2). This magnitude can be easily observed and furthermore manipulated in the state-of-the-art experimental techniques. The proposal suggests a candidate material platform to explore the interplay among spintronics, orbitronics, nonlinear optics, and ferroelectrics in a single platform.