This paper introduces a preview of targeted current research on organic optofluidic materials and devices devoted to 3D photonics microresonators (MRs). First, such an approach takes advantage from a significant know-how on optical simulations of 3D spherical MRs by complementary and coupled ways based on electromagnetism and quantum mechanics principle. Such simulations have allowed to preset the quantization of whispering gallery modes (WGMs) and to define a new formulation of optical caustics in global 3D MRs cavities. Leaning from these simulations, an interdisciplinary approach has been achieved by combining microfluidics techniques and thin layer processes that allowed with flow rates control the realization of 3D droplets MRs of several tens of micrometers in radii. Finally, free-space optical characterizations have been performed on such 3D polymeric MRs by judicious protocols based, respectively, on a modified Raman spectroscopy laser excitation and an adequate direct beam waist optical coupling. Spectral analysis on such 3D MRs of various sizes confirms the excitation of the expected WGMs revealing free spectral range (FSR) and caustics values close to the analytical ones. 1. Introduction Integrated optics [1, 2] plays a key role in sensors applications and optical telecommunication systems such as waveguides, Mach-Zehnder interferometers, modulators, and wavelength filters. An increasing number of these photonic devices are based on polymers materials and are increasingly being used in sensors and telecommunications applications [3–7]. Such organic materials offer numerous advantages as large volume and low cost for mass production facilities due to liquid phase processability. For several years, optical microresonators (MRs) deserve a large attention due to their specific spectral and temporal optical properties required for a wide range of applications and studies such as filtering/demultiplexing wavelength, optical switching, biological sensing, and lasers sources [8–10]. Within such systems under resonance condition, the electromagnetic fields are strongly confined near the surface as quantified modes, sources of intense locations of energy, and so-called whispering gallery modes (WGMs). Various 2D and 2.5D organic shapes have been reported according to the desired functionality including disks, rings, and stadium using thin layer processes and lithography or e-beam techniques [11–15]. The aim of this paper is to investigate a targeted current research on organic optofluidic materials based on spherical 3D MRs. This study includes
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