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1. Neuromorphic photonic networks using silicon photonic weight banks

   https://doi.org/10.1038/s41598-017-07754-z  

   Tait, Alexander N.; de Lima, Thomas Ferreira; Zhou, Ellen; Wu, Allie X.; Nahmias, Mitchell A.; Shastri, Bhavin J.; Prucnal, Paul R. (December 2017, Scientific Reports)
2. Photonic Crystal Enhanced Microscopy on a 2D Photonic Crystal Surface

   https://doi.org/10.1002/admt.202401837  

   Liu, Weinan; Li, Siyan; Chow, Edmond; Bhaskar, Seemesh; Fang, Ying; Cunningham, Brian_T (January 2025, Advanced Materials Technologies)

   Abstract Digital‐resolution biosensing based on resonant reflection from photonic crystals (PC) has demonstrated significant potential for detection of proteomic and genomic biomarkers in serology, infectious disease diagnostics, and cancer diagnostics. An important intrinsic characteristic of resonant metamaterial surfaces is that enhanced electromagnetic fields are not uniformly distributed, resulting in spatially variable light‐matter interactions with nanoparticle tags that signal the presence of biomarker molecules. In this work, the spatial uniformity of resonantly enhanced, surface‐confined electromagnetic fields of a 1D PC is compared with a 2D PC with fourfold symmetry. When illuminated with unpolarized light, the simultaneously excited electromagnetic fields of transverse electric and transverse magnetic modes of the 2D PC present equally strong but complementary spatial distribution, leading to a >100% increased average near‐field intensity accompanied with a >50% compressed standard deviation compared to the 1D PC. Utilizing Photonic Resonator Absorption Microscopy (PRAM) to experimentally measure the absorption uniformity of ≈80 nm gold nanoparticles distributed upon the PC surface, a >100% improvement of the signal uniformity is observed when using the 2D PC. Overall, improvement in AuNP detection contrast, uniformity, and point spread function is demonstrated by PRAM performed upon a 2D PC surface. 

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3. Neuromorphic Photonic Networks

   Shastri, Bhavin J; Bilodeau, Simon; Marquez, Bicky A; Tait, Alexander N; de Lima, Thomas F; Huang, Chaoran; Chrostowski, Lukas; Shekhar, Sudip; Prucnal, Paul R (July 2021, Optical Fiber Communication Conference (OFC))

   Dong, P.; Kani, J.; Xie, C.; Casellas, R.; Cole, C.; Li, M. (Ed.)

   Neuromorphic photonics exploit optical device physics for neuron models, and optical interconnects for distributed, parallel, and analog processing for high-bandwidth, low-latency and low switching energy applications in artificial intelligence and neuromorphic computing. 

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4. High-speed multifunctional photonic memory on a foundry-processed photonic platform

   https://doi.org/10.1364/OPTICA.536866  

   Rahimi_Kari, Sadra; Tamura, Marcus; Guo, Zhimu; Huang, Yi-Siou; Sun, Hongyi; Lian, Chuanyu; Nobile, Nicholas; Erickson, John; Moridsadat, Maryam; Ríos_Ocampo, Carlos_A; et al (January 2025, Optica)

   The integration of computing with memory is essential for distributed, massively parallel, and adaptive architectures such as neural networks in artificial intelligence (AI). Accelerating AI can be achieved through photonic computing, but it requires nonvolatile photonic memory capable of rapid updates during on-chip training sessions or when new information becomes available during deployment. Phase-change materials (PCMs) are promising for providing compact, nonvolatile optical weighting; however, they face limitations in terms of bit precision, programming speed, and cycling endurance. Here, we propose a novel photonic memory cell that merges nonvolatile photonic weighting using PCMs with high-speed, volatile tuning enabled by an integrated PN junction. Our experiments demonstrate that the same PN modulator, fabricated via a foundry-compatible process, can achieve dual functionality. It supports coarse programmability for setting initial optical weights and facilitates high-speed fine-tuning to adjust these weights dynamically. The result shows a 400-fold increase in volatile tuning speed and a 10,000-fold enhancement in efficiency. This multifunctional photonic memory with volatile and nonvolatile capabilities could significantly advance the performance and versatility of photonic memory cells, providing robust solutions for dynamic computing environments. 

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5. Photonic Band Gaps and Resonance Modes in 2D Twisted Moiré Photonic Crystal

   https://doi.org/10.3390/photonics8100408  

   Alnasser, Khadijah; Kamau, Steve; Hurley, Noah; Cui, Jingbiao; Lin, Yuankun (October 2021, Photonics)

   The study of twisted bilayer 2D materials has revealed many interesting physics properties. A twisted moiré photonic crystal is an optical analog of twisted bilayer 2D materials. The optical properties in twisted photonic crystals have not yet been fully elucidated. In this paper, we generate 2D twisted moiré photonic crystals without physical rotation and simulate their photonic band gaps in photonic crystals formed at different twisted angles, different gradient levels, and different dielectric filling factors. At certain gradient levels, interface modes appear within the photonic band gap. The simulation reveals “tic tac toe”-like and “traffic circle”-like modes as well as ring resonance modes. These interesting discoveries in 2D twisted moiré photonic crystal may lead toward its application in integrated photonics. 

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