Extraction of Inherent Amplitude Mode from a Light Beam

Mode extraction is the inverse process of the double‐beam superposition principle in classical optics. While polarization mode extraction has been successfully demonstrated using an m ‐order vector vortex beam, amplitude mode extraction remains a significant challenge due to the complex intertwinement of inherent amplitude modes. To address this challenge, a method is developed to extract arbitrary amplitude modes of a light beam in both the real and imaginary domains. By introducing competition between amplitude modes in these domains, the desired amplitude modes within a light beam can be selectively extracted in the focal region of an objective lens using an optical pen. This work demonstrates the principle of amplitude mode extraction, thereby potentially paving the way for multidimensional manipulation of light fields.