Nanoporous anodic alumina photonic crystals for solid-state lasing systems: state-of-the-art and perspectives

Photonic crystals (PCs)—dielectric materials with a refractive index that is modulated periodically across the space—are essential components for a broad variety of photonic technologies requiring precise light-manipulation capabilities such as telecommunications, sensing, imaging, energy, stealth, and environmental remediation. Of all these, the emission of light from a radiation source embedded within a PC structure has been envisioned for engineering novel forms of light-emitting and quantum optics systems since the formalization of the PC concept by Yablonovitch and Jonh in 1987. Nanoporous anodic alumina (NAA) fabricated by electrochemical oxidation—anodization—of aluminum provides an ideal and versatile effective medium that can be precisely engineered to create multiple forms of PC structures to harness distinct light–matter interactions (e.g., Bragg diffraction, constructive recirculation, confinement, and interference). The nanoporous framework of NAA-PCs can accommodate a range of light-emitting materials as gain media to modulate the properties of emitted light across the optical spectrum. This review provides an up-to-date overview of recent advances in the field of NAA-PC technology, including new anodization strategies and photonic crystal structures, and focuses on their application in light-emitting and lasing systems. We conclude our review with a list of challenges and opportunities, and the future prospects of this exciting field.