Similar to the behavior that materials adopt when they are in nanoscales, alloy nanoparticles show intensified properties and new quantum effects when their relative surface area increases. Metals that are not immiscible at their bulky form can be mixed when they are in nanoscales. This makes it possible to combine bimetallic or multi-metallic nanoparticles like Cu-Au alloy nanoparticles with applications in photonics, catalysis and biomedical field. I fact, one way to increase the stability of some metallic nanoparticles is to create their alloy form through mixing them with some stable metals like Au. There are several methods to synthesize alloy nanoparticles with one as a convenient, simple and general technique through irradiation of the dispersed metal powders in organic or aqueous solutions using unfocused 532nm laser radiation. This results in a homogenous composition to be applied as magnetic nanoparticles and chemical or biological probes. Moreover, the optical and mechanical properties become favorable in specific wavelengths.