Summary: | In this work, the influence of various electrochemical parameters on the production of porous anodic alumina (PAA)-based DBRs (distributed Bragg reflector) during high-temperature-pulse-anodization was studied. It was observed that lowering the temperature from 30 to 27 °C brings about radical changes in the optical performance of the DBRs. The multilayered PAA fabricated at 27 °C did not show optical characteristics typical for DBR. The DBR performance was further tuned at 30 °C. The current recovery (<i>i<sub>a</sub><sup>max</sup></i>) after application of subsequent U<sub>H</sub> pulses started to stabilize upon decreasing high (U<sub>H</sub>) and low (U<sub>L</sub>) voltage pulses, which was reflected in a smaller difference between initial and final thickness of alternating d<sub>H</sub> and d<sub>L</sub> segments (formed under U<sub>H</sub> and U<sub>L</sub>, respectively) and a better DBR performance. Shortening U<sub>H</sub> pulse duration resulted in a progressive shift of photonic stopbands (PSBs) towards the blue part of the spectrum while keeping intensive and symmetric PSBs in the NIR-MIR range. Despite the obvious improvement of the DBR performance by modulation of electrochemical parameters, the problem regarding full control over the homogeneous formation of d<sub>H</sub>+d<sub>L</sub> pairs remains. Solving this problem will certainly lead to the production of affordable and efficient PAA-based photonic crystals with tunable photonic properties in the NIR-MIR region.
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