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GaInNAs has been introduced to design an active switch operating at wavelength <formula formulatype="inline"> <tex Notation="TeX">$\lambda = 1.2855\ \mu\hbox{m}$</tex></formula> having high selectivity. The device is made of a mono-dimensional periodic photonic band-gap structure constituted by alternating ridge waveguide layers with different ridge heights. The periodic waveguiding structure has been designed to show the band gap in correspondence of the wavelength range where the dilute nitride active material experiences maximum gain. As an example, the performances of the switch under electrical control are crosstalk <formula formulatype="inline"><tex Notation="TeX">$\hbox{CT} = -14.1\ \hbox{dB}$</tex></formula>, gain in the on-state <formula formulatype="inline"><tex Notation="TeX">${\rm G} = 7.6\ \hbox{dB}$</tex></formula>, and bandwidth <formula formulatype="inline"><tex Notation="TeX">$\Delta\lambda_{-10\,{\rm dB}} = 1.5\ \hbox{nm}$</tex></formula>. By increasing the input power above the optical threshold value of the gain saturation, the switching performance worsens in terms of crosstalk and gain, but the wavelength selectivity improves, since the bandwidth decreases down to <formula formulatype="inline"><tex Notation="TeX">$\Delta\lambda_{-10\,{\rm dB}} = 0.8\ \hbox{nm}$</tex></formula> for the input optical power <formula formulatype="inline"><tex Notation="TeX">${\rm P}_{i} = 20\ \hbox{mW}$</tex></formula>.