Unclonable Three-Level Holograms for Two-Factor Visual Authentication via One-Step Cascade-Nanostructure Imprinting

J. Yang, M. Choi, J.-H. Ha, J. Ahn, S. H. Hwang, S. Jeon, D. Kim, J. Jeong, M. Kim, H. Lim, B.-H. Kang, J.-A. Choi, B. Kang, H. Kim*, J. Ahn*, and J.-H. Jeong*, Nano Letters, 2026, 26 (30): 9836–9846. (Front cover)