Understanding the interaction between light and matter is fundamental to various scientific and technological advancements, from quantum optics to material science. This study provides a comprehensive exploration of the core principles and progressive steps involved in the physics of light-matter coupling. We begin by outlining the historical context and key theoretical frameworks that have shaped our current understanding, including classical electrodynamics and quantum mechanics. Subsequent sections delve into the essential phenomena such as absorption, emission, and scattering, examining how these processes are influenced by the nature of the interacting materials. The study emphasizes the significance of experimental techniques and theoretical models in elucidating the dynamics of light-matter interactions. By integrating recent advancements and emerging research directions, we aim to present a cohesive overview of the fundamental concepts and practical applications of light-matter coupling. This comprehensive approach not only bridges theoretical knowledge with experimental insights but also highlights future research opportunities in this dynamic field.

Polymer matrix composites have become indispensable materials across numerous industries due to their tunable mechanical, thermal, and electrical properties. Polyvinyl alcohol (PVA), a water-soluble and biocompatible synthetic polymer, is a versatile matrix material for composite development. The incorporation of carbon-based fillers has long been a strategy to enhance polymer properties, ranging from mechanical reinforcement to electrical conductivity [1]. Recent advances in nanotechnology have introduced novel carbon allotropes, such as carbon nanoparticles, including carbon quantum dots (CQDs) [2, 3], carbon nanodots (CNDs) [4], and graphene quantum dots (GQDs) [5]. These nanoparticles exhibit unique size-dependent optical and electronic properties [2, 3, 4, 5, 6] that differ significantly from traditional carbon fillers like graphite [1]. Laser ablation in liquids (LAL) is a promising method for synthesizing such nanoparticles, producing them directly in a liquid medium suitable for composite fabrication. This article reviews the relevant aspects of PVA as a matrix, the characteristics of advanced carbon nanoparticle fillers based on cited literature [2, 3, 4, 5, 6], considers fabrication methods like LAL for producing such fillers, and discusses the potential properties and applications of resulting PVA-carbon nanoparticle composites, drawing parallels and distinctions with other carbon-filled systems [1].

This study presents an innovative approach to implementing vector-matrix multiplication (VMM) using optimized low-index-contrast silicon photonic structures designed via inverse design techniques. Leveraging the inherent parallelism and high bandwidth of silicon photonics, the proposed architecture employs low-index-contrast waveguides to achieve low-loss, high-fidelity signal propagation while maintaining fabrication compatibility with existing CMOS processes. Inverse design algorithms, including adjoint optimization and topology optimization, were utilized to precisely tailor the photonic structures to perform the required linear transformations with minimal crosstalk and insertion loss. Numerical simulations demonstrate that the optimized devices can perform VMM operations with high accuracy, supporting scalability for large-scale photonic computing applications. The results highlight the potential of combining low-index-contrast materials and inverse design to enable efficient, reconfigurable, and compact photonic accelerators for artificial intelligence and signal processing workloads.