SYSTEMATIC ANALYSIS OF DOMINANT FACTORS CONTROLLING PHOTONIC NANOJET PERFORMANCE FOR SUBSTRATE-EMBEDDED HIGH-REFRACTIVE-INDEX MICROSPHERES
Keywords:
Photonic nanojet, High-refractive-index microsphere, Substrate dragging effect, Mie resonanceAbstract
Addressing the physical bottleneck that high-refractive-index materials struggle to overcome whispering-gallery modes (WGMs), this study systematically investigated the optical field evolution laws of silicon-based high-refractive-index microspheres in the 1550 nm band, evaluating the influence of four dimensions: environmental refractive index, substrate coupling, asymmetric substrate dimensions, and microsphere embedding depth. Research indicates that elevating the environmental refractive index to above 2.40 can effectively overcome the “focal retraction” phenomenon induced by extreme refractive index contrast. However, in practical on-chip integration applications, the introduction of the underlying substrate triggers a pronounced “substrate dragging effect,” leading to massive optical field energy dissipation and focal length degradation. Consequently, the microsphere must maintain a shallow embedding (depth less than 0.08 times the microsphere diameter) to sustain a far-field propagating state; simultaneously, asymmetric substrate dimensions exert a significant anisotropic influence on beam focusing. By constructing a global parameter phase diagram, this study identifies the optimal comprehensive optimization interval, providing engineering recommendations for the on-chip integration and structural design of high-refractive-index infrared micro/nano-detectors.References
[1] Rogalski A. Recent progress in infrared detector technologies. Infrared Physics & Technology, 2019, 102: 102976.
[2] Steinvall O K. Performance of laser tracking of small targets during turbulence and beam jitter. Proceedings of SPIE, 2003, 5086.
[3] Downs C, Vandervelde T E. Progress in infrared photodetectors since 2000. Sensors, 2013, 13(4): 5054-5098.
[4] Chen Z, Taflove A, Backman V. Photonic nanojet enhancement of backscattering of light by nanoparticles: a potential novel visible-light ultramicroscopy technique. Optics Express, 2004, 12(7): 1214-1220.
[5] Jia R, Yang Z, Pan X, et al. Study on the characteristics of photonic nanojets generated by non-uniformly coated microspheres. Acta Physica Sinica, 2024, 74(9): 094202.
[6] Yang H, Trouillon R, Huszka G, et al. Super-resolution imaging of a dielectric microsphere is governed by the waist of its photonic nanojet. Nano Letters, 2016, 16(8): 4862-4870.
[7] Liu X, Zhou T, Wang J, et al. Research progress of large field-of-view microsphere lens super-resolution microscopic imaging technology. Infrared and Laser Engineering, 2022, 51(6): 20210438.
[8] McCloskey D, Wang J J, Donegan J F. Low divergence photonic nanojets from Si3N4 microdisks. Optics Express, 2012, 20(1): 128-140.
[9] Luk'yanchuk B S, Paniagua-Domínguez R, Minin I V, et al. Refractive index less than two: photonic nanojets yesterday, today and tomorrow [Invited]. Optical Materials Express, 2017, 7(6): 1820-1847.
[10] Minin I V, Minin O V, Geints Y E. Localized EM and photonic jets from non-spherical and non-symmetrical dielectric mesoscale objects: Brief review. ANNALEN DER PHYSIK, 2015, 527: 491-497.
[11] Sun Z, Liu W, Ge S, et al. Study on photonic nanojets based on double-layer micropyramid structure coupled with spatial light modulation. Acta Photonica Sinica, 2022, 51(12): 1223001.
[12] Veluthandath A V, Murugan G S. Photonic Nanojet Generation Using Integrated Silicon Photonic Chip with Hemispherical Structures. Photonics, 2021, 8(12): 586.
[13] Zhen Z, Huang Y, Feng Y, et al. An ultranarrow photonic nanojet formed by an engineered two-layer microcylinder of high refractive-index materials. Optics Express, 2019, 27(6): 9178-9188.
[14] Gu G, Shao L, Song J, et al. Photonic hooks from Janus microcylinders. Optics Express, 2019, 27(26): 37771-37780.
[15] Amann M C, Bosch T, Lescure M, et al. Laser ranging: a critical review of usual techniques for distance measurement. Optical Engineering, 2001, 40(1): 10-19.
[16] Rogalski A. History of infrared detectors. Opto-Electronics Review, 2012, 20(3): 279-308.
[17] Darafsheh A. Photonic nanojets and their applications. Journal of Physics: Photonics, 2021, 3(2): 022001.
[18] Sun Z, et al. Geometry-Dependent Photonic Nanojet Formation and Arrays Coupling. Nanomaterials, 2026, 16(2): 136.
[19] Geints Y E, Zemlyanov A A, Minin I V. Specular-reflection photonic nanojet. Optics Express, 2020, 28(15): 22690-22704.
[20] Yang M, Wang F, Hao X, et al. Super-resolution imaging and fluorescence enhancement based on microsphere modulated optical field. Laser & Optoelectronics Progress, 2023, 60(10): 1000001.
[21] Ren Y X, et al. Photonic Nanojet Mediated Backaction of Dielectric Microparticles. ACS Photonics, 2020, 7(6): 1483-1490.
[22] Itagi A V, Challener W A. Optics of photonic nanojets. Journal of the Optical Society of America A, 2005, 22(12): 2847-2858.
[23] Devilez A, Bonod N, Wenger J, et al. Three-dimensional subwavelength confinement of light with dielectric microspheres. Optics Express, 2009, 17(4): 2089-2094.
[24] Geints Y E, Zemlyanov A A, Panina E K. Photonic nanojet properties of dielectric microparticles. Journal of the Optical Society of America B, 2011, 28(8): 1825-1830.
[25] Sun M, Duan S, Gao D, et al. Research progress on near-field focusing and far-field imaging simulation of microsphere lenses. Infrared and Laser Engineering, 2022, 51(2): 20220086.