Combining light’s degrees of freedom to see through biological tissues with topology

Abstract

Living tissues absorb and scatter light making imaging and sensing deep within tissues challenging when using only one degree of freedom (DoF) of light. Recently topological light has shown noise invariance by using mappings between light’s different DoFs. Here we show that topological optical skyrmions based on orbital angular momentum (OAM) and polarisation are robust when sent through biological samples. We showcase broad applications, successfully retrieving topology sent through samples with varying composition and distortion strength from fly wings, to butterfly scales to hydra heads. This topological approach precludes the need for aberration correction even when the beam’s spatial structure is destroyed by the biological sample and highlights the power of topological light for seeing through complex organic samples.