With the advancements in technology, reversible logic has been an attractive field of research over the past few years. Reversible logic finds applications in various fields which include optical computing, low power CMOS, digital signal processing, nanotechnology, cryptography, etc. Classical logic circuits result in the release of energy for every bit of information processed. This release of energy even though in small amount may become considerable in the case of complex circuits or systems containing millions of such logic gates. This paper focusses on implementation of a new 3 × 3 reversible logic gate in optical domain using Mach–Zehnder Interferometer. Simulation of the proposed design is carried out in OptiSystem software at a data rate of 10 Gbps. Different applications of the proposed reversible gate along with their performance parameters are also discussed.