TANG, Q. .; XIN, H. . Active Metamaterial Incorporating Gain Device/Medium: A Review. Applied Computational Electromagnetics Society Journal (ACES), [S. l.], v. 29, n. 12, p. 944–959, 2021. Disponível em: https://journals.riverpublishers.com/index.php/ACES/article/view/10791. Acesso em: 23 apr. 2026.