posted on 2022-08-10, 23:40authored bySatyathiran Gunenthiran, Juan Wang, Huong Nguyen Que Tran, Khoa Nhu Tran, Siew Yee Lim, Cheryl Suwen Law, Andrew D. Abell, Zeyad T. Alwahabi, Abel Santos
Random lasing provides new opportunities to engineer
cost-competitive,
highly controllable, and integrable light sources for a broad range
of photonic technologies such as sensing, hyperspectral imaging, high-resolution
spectroscopic analysis, and photonic circuits. In this study, we engineer
the self-organized structure of nanoporous anodic alumina (NAA) through
the electrochemical oxidation of aluminum to generate a palette of
model nanoporous platforms with tailored, hexagonally distributed,
straight cylindrical nanopores. The inner surface of these platforms
is functionalized with a model organic fluorophore via micellar solubilization
of a surfactant. The resultant organic–inorganic composite
structures provide model platforms to develop optically pumped solid-state
random lasers with well-resolved, intense lasing bands. The effect
of NAA’s geometric features on the random lasing characteristics
of these model platforms is elucidated by precisely engineering its
nanopore diameter, nanopore length, interpore distance, and ordering.
Structural engineering of NAA makes it possible to tune and maximize
random-lasing emissions, resulting in strong, polarized lasing at
∼628 nm characterized by a remarkably high-quality-gain product
of ∼1433, a polarization quality of ∼0.9, and a lasing
threshold of ∼0.87 mJ pulse–1.