Realization of Solid Fractional Order Capacitor Using Common Materials

Fractional order element is the most basic components for realization of fractional order systems. A solid fractional order capacitor (FOC) is observed to be capable of replacing bulky ladder RC circuits without altering the system’s behaviour. Instead of an ordinary, conventional and high cost semi-solid FOC, the idea is to design an economically viable solid FOC with low fabrication cost materials like carbon, nail enamel and araldite. This paper describes fabrication of FOC with copper as electrodes and dielectric mix of carbon, nail enamel and araldite, arranged in layers between the two electrodes, with a porous film layer in the middle. The proposed methodology exhibits combination of both resistive and capacitive behaviour, fractionally and for frequencies above 10 kHz, it works as a constant phase element (CPE) with constant phase angle (CPA) of 75o and corresponding $\alpha$ value of 0.8333. The fractional behavior of the fabricated FOC is verified through filter realization with the help of already available Thomas Biquad Model over fractional order Chebyshev lowpass filters.