Interactions of Vectorial Light with Matter

The investigation of spatially structured light, shaped in amplitude, phase and polarization, has been of increasing interest in recent years. Wang et al review all aspects of the interaction of vector light fields with matter but focus specifically on the interaction with atomic gases.

Atomic gases can behave as a highly efficient nonlinear medium since the atoms’ response to an optical field generates a complex polarizability. The complex vector structure of a light field propagation through the atoms is modified by the gas and results in the atomic polarizability modification as a result of the interaction with the structured light, effectively entangling optical field with atomic structures.

The authors point out these holds for the classical as well as the quantum regime. Vector light fields have a higher information content than homogeneously polarized light, making them attractive candidates for information technologies.

An early attempt to connect the polarization structure of an optical beam to the spatial profile of atomic spin alignments was performed via optical pumping in a rubidium vapor. Interaction with the vector light generated light-induced circular dichroism, making the atoms behave like a circular polarizer.

Some years later, the authors of this review demonstrated that cold Rb atoms exposed to vector light could produce spatially resolved electromagnetically induced transparency, which could lead to a form of quantum memory.

“Combining the mature research field of atomic vapors with today’s light shaping technology opens exciting perspectives for communication and sensing applications, and provides fundamental insight into the nature of light-matter interaction,” said author Sonja Franke-Arnold. The authors predict advances in miniaturization and integration for photonic devices that will allow for further technological development of vectorial light-matter interactions.

Source: “Vectorial light-matter inteaction: Exploring spatially structured complex light fields,” by Jinwen Wang, Francesco Castellucci, and Sonja Franke-Arnold, AVS Quantum Science (2020) The article can be accessed at https://doi.org/10.1116/5.0016007 .