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1. Demonstration of Visible-Spectrum-Spanning Integrated Optical-Phased-Array-Based Systems

   https://doi.org/10.1364/CLEO_SI.2025.SS174_6  

   Crawford-Eng, Henry; Coleto, Andres Garcia; Notaros, Jelena (January 2025, Optica Publishing Group)

   We design and experimentally demonstrate the first integrated optical-phased-array-based system that simultaneously emits and controls beams of red, green, and blue light, enabling visible-spectrum-spanning functionality for emerging applications of integrated optical phased arrays that require visible-light operation. 

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2. Design and Demonstration of Grating-Based Antennas for Visible-Light Integrated Optical Phased Arrays

   https://doi.org/10.1364/CLEO_SI.2025.SS186_3  

   Coleto, Andres Garcia; Notaros, Milica; Notaros, Jelena (January 2025, Optica Publishing Group)

   We design and experimentally demonstrate five integrated visible-light grating-based antennas with varying advanced capabilities, including the first visible-light unidirectionally-emitting grating-based antennas for integrated optical phased arrays. 

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3. In-silico predicted mouse melanopsins with blue spectral shifts deliver efficient subcellular signaling

   https://doi.org/10.1186/s12964-024-01753-0  

   Wijayaratna, Dhanushan; Sacchetta, Filippo; Pedraza-González, Laura; Fanelli, Francesca; Sugihara, Tomohiro; Koyanagi, Mitsumasa; Piyawardana, Senuri; Ghotra, Kiran; Thotamune, Waruna; Terakita, Akihisa; et al (December 2024, Cell Communication and Signaling)

   Melanopsin is a photopigment belonging to the G Protein-Coupled Receptor (GPCR) family expressed in a subset of intrinsically photosensitive retinal ganglion cells (ipRGCs) and responsible for a variety of processes. The bistability and, thus, the possibility to function under low retinal availability would make melanopsin a powerful optogenetic tool. Here, we aim to utilize mouse melanopsin to trigger macrophage migration by its subcellular optical activation with localized blue light, while simultaneously imaging the migration with red light. To reduce melanopsin’s red light sensitivity, we employ a combination of in silico structure prediction and automated quantum mechanics/molecular mechanics modeling to predict minimally invasive mutations to shift its absorption spectrum towards the shorter wavelength region of the visible spectrum without compromising the signaling e"ciency. The results demonstrate that it is possible to achieve melanopsin mutants that resist red light-induced activation but are activated by blue light and display properties indicating preserved bistability. Using the A333T mutant, we show that the blue light-induced subcellular melanopsin activation triggers localized PIP3 generation and macrophage migration, which we imaged using red light, demonstrating the optogenetic utility of minimally engineered melanopsins. 

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4. Dual-site occupancy induced broadband cyan emission in Ba ₂ CaB ₂ Si ₄ O ₁₄ :Ce ³⁺

   https://doi.org/10.1039/D0TC02625E  

   You, Shihai; Zhuo, Ya; Chen, Qiulin; Brgoch, Jakoah; Xie, Rong-Jun (November 2020, Journal of Materials Chemistry C)

   null (Ed.)

   There is a significant need to identify cyan-emitting phosphors capable of filling the “cyan-gap” (480–520 nm) in full-visible-spectrum phosphor-converted white light-emitting diodes (pc-wLEDs). Here, a new broadband cyan-emitting phosphor that enables addressing of this challenge is reported. The compound, Ba 2 CaB 2 Si 4 O 14 :Ce 3+ , presents a bright cyan emission peaking at 478 nm with a large full width at half maximum of 142 nm (6053 cm −1 ), and minimal thermal quenching. The photoluminescence properties originate from Ce 3+ residing at two different crystallographic sites, a [BaO 9 ] distorted elongated square pyramid and a [CaO 6 ] trigonal prism. This combination results in an efficient, broad emission covering the blue to green region of the visible spectrum. Fabricating a simple dichromatic ultraviolet ( λ ex = 370 nm) pumped pc-wLED using Ba 2 CaB 2 Si 4 O 14 :Ce 3+ along with a commercially available red phosphor demonstrates full-visible-spectrum white light with high color rendering index ( R a > 90) and tunable correlated color temperature, showing the potential of this material for achieving high-quality LED-based lighting. 

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5. Micromirror based optical phased array for wide-angle beamsteering

   https://doi.org/10.1109/MEMSYS.2017.7863553  

   Wang, Youmin; Wu, Ming C. (February 2017, Micro Electro Mechanical Systems (MEMS), 2017 IEEE 30th International Conference on)

   Optical phased array (OPA) is a key enabling element for solid state LIDAR (light detection and ranging). In this paper, we demonstrate a novel MEMS micromirror array OPA. Vertical combdrive actuators are integrated underneath the mirrors to achieve a small pitch (2.4μm) and a large field of view (22° at 905nm wavelength and 40° at 1550nm). The OPA has 2μs response time, and 10V actuation voltage. 

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