Abstract
Harnessing the full complexity of optical fields requires the complete control of all degrees of freedom within a region of space and time—an open goal for present-day spatial light modulators, active metasurfaces and optical phased arrays. Here, we resolve this challenge with a programmable photonic crystal cavity array enabled by four key advances: (1) near-unity vertical coupling to high-finesse microcavities through inverse design; (2) scalable fabrication by optimized 300 mm full-wafer processing; (3) picometre-precision resonance alignment using automated, closed-loop ‘holographic trimming’; and (4) out-of-plane cavity control via a high-speed μLED array. Combining each, we demonstrate the near-complete spatiotemporal control of a 64 resonator, two-dimensional spatial light modulator with nanosecond- and femtojoule-order switching. Simultaneously operating wavelength-scale modes near the space–bandwidth and time–bandwidth limits, this work opens a new regime of programmability at the fundamental limits of multimode optical control.
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Data availability
The main data supporting the findings of this study are available within the Article and its Supplementary Information. Additional data are available from the corresponding authors upon reasonable request.
Code availability
The SLM control and holography software developed for this study is available online via GitHub at https://github.com/QPG-MIT/slmsuite. A sample finite-difference time-domain simulation is available at https://www.flexcompute.com/userprojects/a-full-degree-of-freedom-spatiotemporal-light-modulator. All the other algorithms are documented within the Article and its Supplementary Information.
Change history
03 January 2023
A Correction to this paper has been published: https://doi.org/10.1038/s41566-022-01145-1
References
Gardner, J. P. et al. The James Webb space telescope. Space Sci. Rev. 123, 485–606 (2006).
Packer, A. M., Roska, B. & Häusser, M. Targeting neurons and photons for optogenetics. Nat. Neurosci. 16, 805–815 (2013).
Demas, J. et al. High-speed, cortex-wide volumetric recording of neuroactivity at cellular resolution using light beads microscopy. Nat. Methods 18, 1103–1111 (2021).
Hamerly, R., Bernstein, L., Sludds, A., Soljačić, M. & Englund, D. Large-scale optical neural networks based on photoelectric multiplication. Phys. Rev. X 9, 021032 (2019).
Bogaerts, W. et al. Programmable photonic circuits. Nature 586, 207–216 (2020).
Wetzstein, G. et al. Inference in artificial intelligence with deep optics and photonics. Nature 588, 39–47 (2020).
Kok, P. et al. Linear optical quantum computing with photonic qubits. Rev. Mod. Phys. 79, 135 (2007).
Ebadi, S. et al. Quantum phases of matter on a 256-atom programmable quantum simulator. Nature 595, 227–232 (2021).
Shaltout, A. M., Shalaev, V. M. & Brongersma, M. L. Spatiotemporal light control with active metasurfaces. Science 364, eaat3100 (2019).
Li, S.-Q. et al. Phase-only transmissive spatial light modulator based on tunable dielectric metasurface. Science 364, 1087–1090 (2019).
Zhang, X., Kwon, K., Henriksson, J., Luo, J. & Wu, M. C. A large-scale microelectromechanical-systems-based silicon photonics LiDAR. Nature 603, 253–258 (2022).
Sun, J., Timurdogan, E., Yaacobi, A., Hosseini, E. S. & Watts, M. R. Large-scale nanophotonic phased array. Nature 493, 195–199 (2013).
Rogers, C. et al. A universal 3D imaging sensor on a silicon photonics platform. Nature 590, 256–261 (2021).
Wu, P. C. et al. Dynamic beam steering with all-dielectric electro-optic III–V multiple-quantum-well metasurfaces. Nat. Commun. 10, 3654 (2019).
Zhang, Y. et al. Electrically reconfigurable non-volatile metasurface using low-loss optical phase-change material. Nat. Nanotechnol. 16, 661–666 (2021).
Park, J. et al. All-solid-state spatial light modulator with independent phase and amplitude control for three-dimensional LiDAR applications. Nat. Nanotechnol. 16, 69–76 (2021).
Wang, Y. et al. Electrical tuning of phase-change antennas and metasurfaces. Nat. Nanotechnol. 16, 667–672 (2021).
Gabor, D. Light and information. Prog. Opt. 1, 109–153 (1961).
Miller, D. A. Fundamental limit to linear one-dimensional slow light structures. Phys. Rev. Lett. 99, 203903 (2007).
Miller, D. A. Attojoule optoelectronics for low-energy information processing and communications. J. Light. Technol. 35, 346–396 (2017).
Panuski, C. L. & Englund, D. R. All-optical spatial light modulators. US patent 11,022,826 (2021).
Soref, R. A. & Bennett, B. R. Electrooptical effects in silicon. IEEE J. Quantum Electron. 23, 123–129 (1987).
Tanabe, T., Taniyama, H. & Notomi, M. Carrier diffusion and recombination in photonic crystal nanocavity optical switches. J. Light. Technol. 26, 1396–1403 (2008).
Panuski, C., Pant, M., Heuck, M., Hamerly, R. & Englund, D. Single photon detection by cavity-assisted all-optical gain. Phys. Rev. B 99, 205303 (2019).
Huang, Y., Hsiang, E.-L., Deng, M.-Y. & Wu, S.-T. Mini-LED, micro-LED and OLED displays: present status and future perspectives. Light Sci. Appl. 9, 105 (2020).
Lin, J. & Jiang, H. Development of microLED. Appl. Phys. Lett. 116, 100502 (2020).
Templier, F. et al. High-resolution active-matrix 10-µm pixel-pitch GaN LED microdisplays for augmented reality applications. In Proc. SPIE 10556, Advances in Display Technologies VIII 10556, 105560I (SPIE, 2018).
Chen, C.-J., Chen, H.-C., Liao, J.-H., Yu, C.-J. & Wu, M.-C. Fabrication and characterization of active-matrix 960 × 540 blue GaN-based micro-LED display. IEEE J. Quantum Electron. 55, 3300106 (2019).
Herrnsdorf, J. et al. Active-matrix GaN micro light-emitting diode display with unprecedented brightness. IEEE Trans. Electron Devices 62, 1918–1925 (2015).
Ferreira, R. X. G. et al. High bandwidth GaN-based micro-LEDs for multi-Gb/s visible light communications. IEEE Photon. Technol. Lett. 28, 2023–2026 (2016).
Cai, Y. et al. Direct epitaxial approach to achieve a monolithic on-chip integration of a HEMT and a single micro-LED with a high-modulation bandwidth. ACS Appl. Electron. Mater. 3, 445–450 (2021).
Park, J. et al. Electrically driven mid-submicrometre pixelation of InGaN micro-light-emitting diode displays for augmented-reality glasses. Nat. Photon. 15, 449–455 (2021).
Hassan, N. B. et al. Ultra-high frame rate digital light projector using chipscale LED-on-CMOS technology. Photonics Res. 10, 2434–2446 (2022).
Miller, D. A. Optical interconnects to electronic chips. Appl. Opt. 49, F59–F70 (2010).
Horie, Y., Arbabi, A., Arbabi, E., Kamali, S. M. & Faraon, A. High-speed, phase-dominant spatial light modulation with silicon-based active resonant antennas. ACS Photonics 5, 1711–1717 (2017).
Peng, C., Hamerly, R., Soltani, M. & Englund, D. R. Design of high-speed phase-only spatial light modulators with two-dimensional tunable microcavity arrays. Opt. Express 27, 30669–30680 (2019).
Lee, H. et al. Local tuning of photonic crystal nanocavity modes by laser-assisted oxidation. Appl. Phys. Lett. 95, 191109 (2009).
Chen, C. J. et al. Selective tuning of high-Q silicon photonic crystal nanocavities via laser-assisted local oxidation. Opt. Express 19, 12480–12489 (2011).
Nozaki, K. et al. Sub-femtojoule all-optical switching using a photonic-crystal nanocavity. Nat. Photon. 4, 477–483 (2010).
Tran, N.-V.-Q., Combrié, S. & De Rossi, A. Directive emission from high-Q photonic crystal cavities through band folding. Phys. Rev. B 79, 041101 (2009).
Tran, N.-V.-Q., Combrié, S., Colman, P., De Rossi, A. & Mei, T. Vertical high emission in photonic crystal nanocavities by band-folding design. Phys. Rev. B 82, 075120 (2010).
Portalupi, S. L. et al. Planar photonic crystal cavities with far-field optimization for high coupling efficiency and quality factor. Opt. Express 18, 16064–16073 (2010).
Qiu, C., Chen, J., Xia, Y. & Xu, Q. Active dielectric antenna on chip for spatial light modulation. Sci. Rep. 2, 855 (2012).
Hansen, R. C. Fundamental limitations in antennas. Proc. IEEE 69, 170–182 (1981).
Fahrenkopf, N. M. et al. The AIM Photonics MPW: a highly accessible cutting edge technology for rapid prototyping of photonic integrated circuits. IEEE J. Sel. Topics Quantum Electron. 25, 8201406 (2019).
Asano, T., Song, B.-S. & Noda, S. Analysis of the experimental Q factors (~1 million) of photonic crystal nanocavities. Opt. Express 14, 1996–2002 (2006).
Kim, S.-H., Kim, S.-K. & Lee, Y.-H. Vertical beaming of wavelength-scale photonic crystal resonators. Phys. Rev. B 73, 235117 (2006).
Sekoguchi, H., Takahashi, Y., Asano, T. & Noda, S. Photonic crystal nanocavity with a Q-factor of ~9 million. Opt. Express 22, 916–924 (2014).
Taguchi, Y., Takahashi, Y., Sato, Y., Asano, T. & Noda, S. Statistical studies of photonic heterostructure nanocavities with an average Q factor of three million. Opt. Express 19, 11916–11921 (2011).
Minkov, M., Dharanipathy, U. P., Houdré, R. & Savona, V. Statistics of the disorder-induced losses of high-Q photonic crystal cavities. Opt. Express 21, 28233–28245 (2013).
Haus, H. A. Waves and fields in optoelectronics. Prentice-Hall Series in Solid State Physical Electronics (1984).
Zhang, S. et al. 1.5 Gbit/s multi-channel visible light communications using CMOS-controlled GaN-based LEDs. J. Light. Technol. 31, 1211–1216 (2013).
McKendry, J. J. et al. Individually addressable alingan micro-LED arrays with CMOS control and subnanosecond output pulses. IEEE Photon. Technol. Lett. 21, 811–813 (2009).
Lan, H.-Y. et al. High-speed integrated micro-LED array for visible light communication. Opt. Lett. 45, 2203–2206 (2020).
Pandey, A. & Mi, Z. III-nitride nanostructures for high efficiency micro-LEDs and ultraviolet optoelectronics. IEEE J. Quantum Electron. 58, 3300313 (2022).
Barclay, P. E., Srinivasan, K. & Painter, O. Nonlinear response of silicon photonic crystal microresonators excited via an integrated waveguide and fiber taper. Opt. Express 13, 801–820 (2005).
Winzer, P. J. & Essiambre, R.-J. Advanced modulation formats for high-capacity optical transport networks. J. Light. Technol. 24, 4711–4728 (2006).
Minkov, M., Savona, V. & Gerace, D. Photonic crystal slab cavity simultaneously optimized for ultra-high Q/V and vertical radiation coupling. Appl. Phys. Lett. 111, 131104 (2017).
Heilmeier, G. H., Zanoni, L. A. & Barton, L. A. Dynamic scattering: a new electrooptic effect in certain classes of nematic liquid crystals. Proc. IEEE 56, 1162–1171 (1968).
Zhang, Z., You, Z. & Chu, D. Fundamentals of phase-only liquid crystal on silicon (LCOS) devices. Light Sci. Appl. 3, e213 (2014).
Ren, Y.-X., Lu, R.-D. & Gong, L. Tailoring light with a digital micromirror device. Ann. Phys. 527, 447–470 (2015).
Hornbeck, L. J. 128 × 128 deformable mirror device. IEEE Trans. Electron Devices 30, 539–545 (1983).
Greenlee, C. et al. Electro-optic polymer spatial light modulator based on a Fabry–Perot interferometer configuration. Opt. Express 19, 12750–12758 (2011).
Yang, W. et al. High speed optical phased array using high contrast grating all-pass filters. Opt. Express 22, 20038–20044 (2014).
Wang, Y. et al. 2D broadband beamsteering with large-scale MEMS optical phased array. Optica 6, 557–562 (2019).
Tzang, O. et al. Wavefront shaping in complex media with a 350 kHz modulator via a 1D-to-2D transform. Nat. Photon. 13, 788–793 (2019).
Chung, S., Abediasl, H. & Hashemi, H. A monolithically integrated large-scale optical phased array in silicon-on-insulator CMOS. IEEE J. Solid-State Circuits 53, 275–296 (2017).
Poulton, C. V. et al. Long-range LiDAR and free-space data communication with high-performance optical phased arrays. IEEE J. Sel. Topics Quantum Electron. 25, 7700108 (2019).
Wang, Q. et al. Optically reconfigurable metasurfaces and photonic devices based on phase change materials. Nat. Photon. 10, 60–65 (2016).
Arbabi, E. et al. MEMS-tunable dielectric metasurface lens. Nat. Commun. 9, 812 (2018).
Smolyaninov, A., El Amili, A., Vallini, F., Pappert, S. & Fainman, Y. Programmable plasmonic phase modulation of free-space wavefronts at gigahertz rates. Nat. Photon. 13, 431–435 (2019).
Shirmanesh, G. K., Sokhoyan, R., Wu, P. C. & Atwater, H. A. Electro-optically tunable multifunctional metasurfaces. ACS Nano 14, 6912–6920 (2020).
Benea-Chelmus, I.-C. et al. Electro-optic spatial light modulator from an engineered organic layer. Nat. Commun. 12, 5928 (2021).
Kim, T. et al. A single-chip optical phased array in a wafer-scale silicon photonics/CMOS 3D-integration platform. IEEE J. Solid-State Circuits 54, 3061–3074 (2019).
Poulton, C. V. et al. 8192-element optical phased array with 100° steering range and flip-chip CMOS. In Conference on Lasers and Electro-Optics, OSA Technical Digest JTh4A.3 (Optical Society of America, 2020).
Fatemi, R., Khachaturian, A. & Hajimiri, A. A nonuniform sparse 2D large-FOV optical phased array with a low-power PWM drive. IEEE J. Solid-State Circuits 54, 1200–1215 (2019).
Ito, H. et al. Wide beam steering by slow-light waveguide gratings and a prism lens. Optica 7, 47–52 (2020).
Huang, Y.-W. et al. Gate-tunable conducting oxide metasurfaces. Nano Lett. 16, 5319–5325 (2016).
Shuai, Y.-C. et al. Coupled bilayer photonic crystal slab electro-optic spatial light modulators. IEEE Photon. J. 9, 7101411 (2017).
Ye, X. et al. High-speed programmable lithium niobate thin film spatial light modulator. Opt. Letters 46, 1037–1040 (2021).
Vercruysse, D., Sapra, N. V., Yang, K. Y. & Vuckovic, J. Inverse-designed photonic crystal circuits for optical beam steering. ACS Photonics 8, 3085–3093 (2021).
Tamanuki, T., Ito, H. & Baba, T. Thermo-optic beam scanner employing silicon photonic crystal slow-light waveguides. J. Light. Technol. 39, 904–911 (2021).
Sakata, R. et al. Dually modulated photonic crystals enabling high-power high-beam-quality two-dimensional beam scanning lasers. Nat. Commun. 11, 3487 (2020).
Minkov, M. & Savona, V. Automated optimization of photonic crystal slab cavities. Sci. Rep. 4, 5124 (2014).
Minkov, M. et al. Inverse design of photonic crystals through automatic differentiation. ACS Photonics 7, 1729–1741 (2020).
Andreani, L. C. & Gerace, D. Photonic-crystal slabs with a triangular lattice of triangular holes investigated using a guided-mode expansion method. Phys. Rev. B 73, 235114 (2006).
Panuski, C., Englund, D. & Hamerly, R. Fundamental thermal noise limits for optical microcavities. Phys. Rev. X 10, 041046 (2020).
Lie, L. N., Razouk, R. R. & Deal, B. E. High pressure oxidation of silicon in dry oxygen. J. Electrochem. Soc. 129, 2828 (1982).
Carreira, J. et al. Gigabit per second visible light communication based on AlGaInP red micro-LED micro-transfer printed onto diamond and glass. Opt. Express 28, 12149–12156 (2020).
Shaltout, A. M. et al. Spatiotemporal light control with frequency-gradient metasurfaces. Science 365, 374–377 (2019).
Pahlevaninezhad, H. et al. Nano-optic endoscope for high-resolution optical coherence tomography in vivo. Nat. Photon. 12, 540–547 (2018).
Watts, M. R., Shaw, M. J. & Nielson, G. N. Microphotonic thermal imaging. Nat. Photon. 1, 632–634 (2007).
Grace, M. R., Dutton, Z., Ashok, A. & Guha, S. Approaching quantum-limited imaging resolution without prior knowledge of the object location. J. Opt. Soc. Am. A 37, 1288–1299 (2020).
Mosk, A. P., Lagendijk, A., Lerosey, G. & Fink, M. Controlling waves in space and time for imaging and focusing in complex media. Nat. Photon. 6, 283–292 (2012).
Yoon, S. et al. Deep optical imaging within complex scattering media. Nat. Rev. Phys. 2, 141–158 (2020).
Bourassa, J. E. et al. Blueprint for a scalable photonic fault-tolerant quantum computer. Quantum 5, 392 (2021).
Bartolucci, S. et al. Fusion-based quantum computation. Preprint at https://arxiv.org/abs/2101.09310 (2021).
Heuck, M., Jacobs, K. & Englund, D. R. Controlled-phase gate using dynamically coupled cavities and optical nonlinearities. Phys. Rev. Lett. 124, 160501 (2020).
Krastanov, S. et al. Room-temperature photonic logical qubits via second-order nonlinearities. Nat. Commun. 12, 191 (2021).
Dostart, N. et al. Serpentine optical phased arrays for scalable integrated photonic lidar beam steering. Optica 7, 726–733 (2020).
Aflatouni, F., Abiri, B., Rekhi, A. & Hajimiri, A. Nanophotonic projection system. Opt. Express 23, 21012–21022 (2015).
Junique, S. et al. GaAs-based multiple-quantum-well spatial light modulators fabricated by a wafer-scale process. Appl. Opt. 44, 1635–1641 (2005).
Yaacobi, A. et al. Integrated phased array for wide-angle beam steering. Opt. Lett. 39, 4575–4578 (2014).
Bartlett, T. A., McDonald, W. C. & Hall, J. N. Adapting Texas Instruments DLP technology to demonstrate a phase spatial light modulator. In Proc. SPIE 10932, Emerging Digital Micromirror Device Based Systems and Applications XI 10932, 109320S (SPIE, 2019).
Shrauger, V. & Warde, C. Development of a high-speed high-fill-factor phase-only spatial light modulator. In Proc. SPIE 4291, Diffractive and Holographic Technologies for Integrated Photonic Systems 4291, 101–108 (SPIE, 2001).
Li, J., Yu, P., Zhang, S. & Liu, N. Electrically-controlled digital metasurface device for light projection displays. Nat. Commun. 11, 3574 (2020).
Marshel, J. H. et al. Cortical layer–specific critical dynamics triggering perception. Science 365, eaaw5202 (2019).
McKnight, D. J., Johnson, K. M. & Serati, R. A. 256 × 256 liquid-crystal-on-silicon spatial light modulator. Appl. Opt. 33, 2775–2784 (1994).
Jayatilleka, H. et al. Post-fabrication trimming of silicon photonic ring resonators at wafer-scale. J. Light. Technol. 39, 5083–5088 (2021).
Biryukova, V., Sharp, G. J., Klitis, C. & Sorel, M. Trimming of silicon-on-insulator ring-resonators via localized laser annealing. Opt. Express 28, 11156–11164 (2020).
Hagan, D. E., Torres-Kulik, B. & Knights, A. P. Post-fabrication trimming of silicon ring resonators via integrated annealing. IEEE Photon. Technol. Lett. 31, 1373–1376 (2019).
Han, S. & Shi, Y. Post-fabrication trimming of photonic crystal nanobeam cavities by electron beam irradiation. Opt. Express 26, 15908–15913 (2018).
Gil-Santos, E. et al. Scalable high-precision tuning of photonic resonators by resonant cavity-enhanced photoelectrochemical etching. Nat. Commun. 8, 14267 (2017).
Spector, S., Knecht, J. M. & Juodawlkis, P. W. Localized in situ cladding annealing for post-fabrication trimming of silicon photonic integrated circuits. Opt. Express 24, 5996–6003 (2016).
Lipka, T., Kiepsch, M., Trieu, H. K. & Müller, J. Hydrogenated amorphous silicon photonic device trimming by UV-irradiation. Opt. Express 22, 12122–12132 (2014).
Atabaki, A. H., Eftekhar, A. A., Askari, M. & Adibi, A. Accurate post-fabrication trimming of ultra-compact resonators on silicon. Opt. Express 21, 14139–14145 (2013).
Cai, T., Bose, R., Solomon, G. S. & Waks, E. Controlled coupling of photonic crystal cavities using photochromic tuning. Appl. Phys. Lett. 102, 141118 (2013).
Hennessy, K., Högerle, C., Hu, E., Badolato, A. & Imamoğlu, A. Tuning photonic nanocavities by atomic force microscope nano-oxidation. Appl. Phys. Lett. 89, 041118 (2006).
Acknowledgements
We thank the MITRE Quantum Moonshot Program for program oversight, Flexcompute for supporting finite-difference time-domain simulations, the MIT.nano staff for fabrication assistance, and M. ElKabbash (MIT) for useful discussions. C.L.P. was supported by the Hertz Foundation Elizabeth and Stephen Fantone Family Fellowship. I.C. was supported by the National Defense Science and Engineering Graduate Fellowship Program and the National Science Foundation (NSF) award DMR-1747426. S.T.-M. is funded by the Schmidt Postdoctoral Award and the Israeli Vatat Scholarship. Experiments were supported in part by Army Research Office grant W911NF-20-1-0084 (D.R.E.), supervised by M. Gerhold; the Air Force Research Laboratory under agreements FA8650-21-2-1000 and FA8750-21-2-0004; the Engineering and Physical Sciences Research Council grants EP/M01326X/1 and EP/T00097X/1 (M.D.D. and M.J.S.); and the Royal Academy of Engineering Research Chairs and Senior Research Fellowships (M.J.S.). This material is based on the research sponsored by the Air Force Research Laboratory under agreement no. FA8650-21-2-1000. The US Government is authorized to reproduce and distribute reprints for governmental purposes notwithstanding any copyright notation thereon. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of the United States Air Force, the Air Force Research Laboratory or the US Government.
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Contributions
C.L.P. and D.R.E. conceived the idea, developed the theory and led the research. M.M. and C.L.P. developed the far-field optimization technique and designs. C.J.B. developed the optimized the resonator detuning theory. C.L.P. conducted the experiments with assistance from I.C. (trimming experiments), S.T.-M. (holography software) and A.D.G. (μLED measurements). J.J.D.M., M.D.D. and M.J.S. contributed the μLED arrays and guided the incoherent switching experiments. C.H. and J.N.W.-B. fabricated the initial samples for evaluation before foundry process development by C.T., J.S.L., J.M. and G.L.L. S.F.P. assisted with the wafer post-processing. M.L.F. coordinated and led the foundry fabrication with assistance from G.L.L. and D.J.C. C.L.P. wrote the manuscript with input from all the authors.
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C.L.P. and D.R.E. are authors of US patent 11,022,826 (all-optical spatial light modulators) and US patent App. 16/876,477 (high-speed wavelength-scale spatial light modulators with two-dimensional tunable microcavity arrays) that outline the all-optical control scheme and resonant architecture of the PhC-SLM developed here. The other authors declare no competing interests.
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Extended data
Extended Data Fig. 1 Optimized holography with inverse-designed, vertically-coupled microcavity arrays.
(a) Silicon L3 slab defect cavity design (hexagonal lattice constant a = 0.4μm; hole radius r/a = 0.25; slab thickness t = 220 nm) with overlaid midplane magnetic field profile Hz after Q optimization by displacing (δxi, δyi) and resizing (δri) the shaded holes in the \(16a\times 16(\sqrt{3}/2)a\) periodic unit cell. Hole shifts are magnified by 3 × for visualization. The confined cavity mode radiates into the broad far-field profile in (b, background), violating (C1) and yielding a zero-order diffraction efficiency η0 ≪ 1. As a result, simulated trial holograms (c) from a 64 × 64 cavity array with optimized detunings (Supplement Section D) have minimal overall diffraction efficiency η. Inverse design (b) solves these problems. Guided mode expansion (GME) approximates the mode’s Q and far-field profile by sampling the losses {c} at the array’s diffraction orders (white × s) displaced by Bloch boundary conditions \({\overrightarrow{k}}_{i}\) (that is at the coloured dots). An objective function f that maximizes Q, confines \(\overrightarrow{H}\), and minimizes {c} at any non-zero diffraction order can then be efficiently optimized with respect to all hole parameters using reverse-mode automatic differentiation (b). The resulting devices with high-Q, efficient coupling, and directional emission enable high-performance (η ~ 1) resonant holography (d).
Extended Data Fig. 2 Overview of experimental setups for measuring and controlling the photonic crystal SLM (PhC-SLM).
A cross-polarized microscope (a) featuring balanced homodyne measurement (b) enables near- and far-field characterization of cavity arrays controlled by SLM-distributed coherent light (c) or high-speed incoherent μLED arrays (d). TL: tunable infrared laser (Santec TSL-710), EOM: electro-optic amplitude modulator; λ/2: half-wave plate, PBS: polarizing beamsplitter; L1: 250 mm back-focal-plane lens; DM: long-pass dichroic mirror; OL: objective lens (Nikon Plan Fluor 40 × /0.60 NA or Nikon LU Plan 100 × /0.95 NA), L2: 250 mm back-focal-plane lens; SF: spatial filter; L3: 200 mm tube lens; v-SWIR: visible-short wave infrared camera (Xenics Cheetah 640); DAQ: data acquisition unit (NI USB-6343); Δt: trigger delay generator (SRS DG645); LO: local oscillator; PM: piezo mirror; BD: balanced detector (Thorlabs PDB480C-AC); Phase Lock: TEM LaseLock; LPF: low-pass filter; CWTL: continuous-wave trimming laser (Coherent Verdi V18); MLD: modulated laser diode (Hubner Cobolt or PicoLAS LDP); BE: 5 × visible beam expander; LCOS: high-power liquid crystal SLM (Santec SLM-300); L4: 300 mm; L5: 250 mm; PD: photo-detector; CL: collection lens (Zeiss Fluar 5 × /0.25 NA); VBE: 0.5 × − 2 × variable beam expander; DP: dove prism.
Extended Data Fig. 3 Cross-polarized back-focal-plane (BFP) imaging techniques for a grating-coupled L3 cavity.
Two orthogonally polarized far-field profiles are imaged by orienting the input polarization Ein at a + 45∘ (a) or − 45∘ (b) angle from the dominant cavity polarization axis (dashed line in inset). The complete cavity emission profile \(S(\overrightarrow{k})\) can be reconstructed by summing both images (c) or approximated from a single polarized image (d), yielding near-identical images with quantitative agreement between the extracted η0.
Extended Data Fig. 4 Imaged far-field profiles \(S(\overrightarrow{k})\) (over a 0.9 numerical aperture) for each device in an 8 × 8 array of inverse designed (top) and grating-coupled (bottom) L3 PhC cavities.
The extracted zero-order efficiencies η0 and standard deviations are also provided.
Extended Data Fig. 5 Flowchart of the holographic trimming algorithm.
Trimming holograms are formed with weighted Gerchberg-Saxton (GS) algorithms and projected onto desired cavities for duration Δt with power \({P}_{{{{\rm{trim}}}}}\). Alternating trimming and resonance readout periods continue until the instantaneous wavelength λi of any targeted cavity blueshifts past the target wavelength λt. Thereafter, a new set of target cavities is selected and trimmed. This selection and trimming sub-loop continues until all resonant wavelengths {λ0} are below the ‘rest’ wavelength λrest, at which point trimming is halted and the resonances are continuously monitored at readout interval Δtrest. When the resonances are sufficiently stable (redshifting from moisture adsorption to the silicon membrane is arrested), the total ‘rehydration’ redshift Δλ0 of each cavity is updated to better estimate the true resonant wavelength λ0 ≈ λi + Δλ0 from the instantaneous wavelengths {λi} during trimming. The entire process terminates when the peak-to-peak static resonant wavelength uniformity \(\Delta {\lambda }_{0}^{{{{\rm{p-p}}}}}\) drops below the desired tolerance Δλtol.
Extended Data Fig. 6 Overlaid images of 10×10 cavity (grey) and trimming spot (colour) arrays demonstrating the ≪ μm placement accuracy and percent-order power uniformity of weighted Gerchberg-Saxton phase retrieval with experimental camera feedback.
In general, our holography software (Supplement Section F) creates high-uniformity optical foci to arbitrary image plane locations specified by the user.
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Supplementary Sections A–G, Figs. 1–8 and Table 1.
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Panuski, C.L., Christen, I., Minkov, M. et al. A full degree-of-freedom spatiotemporal light modulator. Nat. Photon. 16, 834–842 (2022). https://doi.org/10.1038/s41566-022-01086-9
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DOI: https://doi.org/10.1038/s41566-022-01086-9
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