Experimental demonstration of an all-optical NOT logic gate based on combined Brillouin gain and loss in an optical fiber

An all-optical NOT logic gate, based on combined Brillouin gain and loss in an optical fiber, has been experimentally demonstrated. An input (IN) to the NOT gate is a probe wave, which is a combination of a Stokes and anti-Stokes waves, and the output (OUT) is a pump wave. The probe and pump waves undergo a combined Brillouin gain and loss interaction in an optical fiber of 20.56 km length, which enables the switching mechanism of the NOT gate. A switching contrast of 43-45% has been achieved when the power of the input probe wave was decreased from 1.4 mW to 30 µW, yielding an increasing power of the output pump wave from 0.75 mW to 1.4 mW. The experimental results are in line with previously published theoretical simulations of the all-optical NOT logic gate.