Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

A full degree-of-freedom spatiotemporal light modulator

A Publisher Correction to this article was published on 03 January 2023

This article has been updated

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.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Full DoF spatiotemporal optical programming.
Fig. 2: The PhC-SLM.
Fig. 3: Conventional versus inverse-designed PhC cavities.
Fig. 4: Full-wafer photonic crystal fabrication in an optimized 300 mm foundry process.
Fig. 5: Parallel, fully automated and low-loss microcavity trimming via structured laser oxidation.
Fig. 6: Nanosecond switching and spatial light modulation.

Similar content being viewed by others

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

References

  1. Gardner, J. P. et al. The James Webb space telescope. Space Sci. Rev. 123, 485–606 (2006).

    Article  ADS  Google Scholar 

  2. Packer, A. M., Roska, B. & Häusser, M. Targeting neurons and photons for optogenetics. Nat. Neurosci. 16, 805–815 (2013).

    Article  Google Scholar 

  3. 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).

    Article  Google Scholar 

  4. 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).

    Google Scholar 

  5. Bogaerts, W. et al. Programmable photonic circuits. Nature 586, 207–216 (2020).

    Article  ADS  Google Scholar 

  6. Wetzstein, G. et al. Inference in artificial intelligence with deep optics and photonics. Nature 588, 39–47 (2020).

    Article  ADS  Google Scholar 

  7. Kok, P. et al. Linear optical quantum computing with photonic qubits. Rev. Mod. Phys. 79, 135 (2007).

    Article  ADS  Google Scholar 

  8. Ebadi, S. et al. Quantum phases of matter on a 256-atom programmable quantum simulator. Nature 595, 227–232 (2021).

    Article  ADS  Google Scholar 

  9. Shaltout, A. M., Shalaev, V. M. & Brongersma, M. L. Spatiotemporal light control with active metasurfaces. Science 364, eaat3100 (2019).

    Article  ADS  Google Scholar 

  10. Li, S.-Q. et al. Phase-only transmissive spatial light modulator based on tunable dielectric metasurface. Science 364, 1087–1090 (2019).

    Article  ADS  Google Scholar 

  11. 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).

    Article  ADS  Google Scholar 

  12. Sun, J., Timurdogan, E., Yaacobi, A., Hosseini, E. S. & Watts, M. R. Large-scale nanophotonic phased array. Nature 493, 195–199 (2013).

    Article  ADS  Google Scholar 

  13. Rogers, C. et al. A universal 3D imaging sensor on a silicon photonics platform. Nature 590, 256–261 (2021).

    Article  ADS  Google Scholar 

  14. Wu, P. C. et al. Dynamic beam steering with all-dielectric electro-optic III–V multiple-quantum-well metasurfaces. Nat. Commun. 10, 3654 (2019).

    Article  ADS  Google Scholar 

  15. Zhang, Y. et al. Electrically reconfigurable non-volatile metasurface using low-loss optical phase-change material. Nat. Nanotechnol. 16, 661–666 (2021).

    Article  ADS  Google Scholar 

  16. 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).

    Article  ADS  Google Scholar 

  17. Wang, Y. et al. Electrical tuning of phase-change antennas and metasurfaces. Nat. Nanotechnol. 16, 667–672 (2021).

    Article  ADS  Google Scholar 

  18. Gabor, D. Light and information. Prog. Opt. 1, 109–153 (1961).

  19. Miller, D. A. Fundamental limit to linear one-dimensional slow light structures. Phys. Rev. Lett. 99, 203903 (2007).

    Article  ADS  Google Scholar 

  20. Miller, D. A. Attojoule optoelectronics for low-energy information processing and communications. J. Light. Technol. 35, 346–396 (2017).

    Article  ADS  Google Scholar 

  21. Panuski, C. L. & Englund, D. R. All-optical spatial light modulators. US patent 11,022,826 (2021).

  22. Soref, R. A. & Bennett, B. R. Electrooptical effects in silicon. IEEE J. Quantum Electron. 23, 123–129 (1987).

    Article  ADS  Google Scholar 

  23. Tanabe, T., Taniyama, H. & Notomi, M. Carrier diffusion and recombination in photonic crystal nanocavity optical switches. J. Light. Technol. 26, 1396–1403 (2008).

    Article  ADS  Google Scholar 

  24. 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).

    Article  ADS  Google Scholar 

  25. 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).

    Article  ADS  Google Scholar 

  26. Lin, J. & Jiang, H. Development of microLED. Appl. Phys. Lett. 116, 100502 (2020).

    Article  ADS  Google Scholar 

  27. 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).

  28. 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).

    Article  Google Scholar 

  29. Herrnsdorf, J. et al. Active-matrix GaN micro light-emitting diode display with unprecedented brightness. IEEE Trans. Electron Devices 62, 1918–1925 (2015).

    Article  ADS  Google Scholar 

  30. 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).

    Article  ADS  Google Scholar 

  31. 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).

    Article  Google Scholar 

  32. 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).

    Article  ADS  Google Scholar 

  33. Hassan, N. B. et al. Ultra-high frame rate digital light projector using chipscale LED-on-CMOS technology. Photonics Res. 10, 2434–2446 (2022).

    Article  ADS  Google Scholar 

  34. Miller, D. A. Optical interconnects to electronic chips. Appl. Opt. 49, F59–F70 (2010).

    Article  Google Scholar 

  35. 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).

    Article  Google Scholar 

  36. 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).

    Article  ADS  Google Scholar 

  37. Lee, H. et al. Local tuning of photonic crystal nanocavity modes by laser-assisted oxidation. Appl. Phys. Lett. 95, 191109 (2009).

    Article  ADS  Google Scholar 

  38. 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).

    Article  ADS  Google Scholar 

  39. Nozaki, K. et al. Sub-femtojoule all-optical switching using a photonic-crystal nanocavity. Nat. Photon. 4, 477–483 (2010).

    Article  ADS  Google Scholar 

  40. 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).

    Article  ADS  Google Scholar 

  41. 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).

    Article  ADS  Google Scholar 

  42. 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).

    Article  ADS  Google Scholar 

  43. Qiu, C., Chen, J., Xia, Y. & Xu, Q. Active dielectric antenna on chip for spatial light modulation. Sci. Rep. 2, 855 (2012).

    Article  ADS  Google Scholar 

  44. Hansen, R. C. Fundamental limitations in antennas. Proc. IEEE 69, 170–182 (1981).

    Article  ADS  Google Scholar 

  45. 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).

    Article  Google Scholar 

  46. 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).

    Article  ADS  Google Scholar 

  47. Kim, S.-H., Kim, S.-K. & Lee, Y.-H. Vertical beaming of wavelength-scale photonic crystal resonators. Phys. Rev. B 73, 235117 (2006).

    Article  ADS  Google Scholar 

  48. Sekoguchi, H., Takahashi, Y., Asano, T. & Noda, S. Photonic crystal nanocavity with a Q-factor of ~9 million. Opt. Express 22, 916–924 (2014).

    Article  ADS  Google Scholar 

  49. 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).

    Article  ADS  Google Scholar 

  50. 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).

    Article  ADS  Google Scholar 

  51. Haus, H. A. Waves and fields in optoelectronics. Prentice-Hall Series in Solid State Physical Electronics (1984).

  52. 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).

    Article  ADS  Google Scholar 

  53. 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).

    Article  ADS  Google Scholar 

  54. Lan, H.-Y. et al. High-speed integrated micro-LED array for visible light communication. Opt. Lett. 45, 2203–2206 (2020).

    Article  ADS  Google Scholar 

  55. Pandey, A. & Mi, Z. III-nitride nanostructures for high efficiency micro-LEDs and ultraviolet optoelectronics. IEEE J. Quantum Electron. 58, 3300313 (2022).

  56. 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).

    Article  ADS  Google Scholar 

  57. Winzer, P. J. & Essiambre, R.-J. Advanced modulation formats for high-capacity optical transport networks. J. Light. Technol. 24, 4711–4728 (2006).

    Article  ADS  Google Scholar 

  58. 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).

    Article  ADS  Google Scholar 

  59. 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).

    Article  Google Scholar 

  60. Zhang, Z., You, Z. & Chu, D. Fundamentals of phase-only liquid crystal on silicon (LCOS) devices. Light Sci. Appl. 3, e213 (2014).

    Article  ADS  Google Scholar 

  61. Ren, Y.-X., Lu, R.-D. & Gong, L. Tailoring light with a digital micromirror device. Ann. Phys. 527, 447–470 (2015).

    Article  MathSciNet  Google Scholar 

  62. Hornbeck, L. J. 128 × 128 deformable mirror device. IEEE Trans. Electron Devices 30, 539–545 (1983).

    Article  ADS  Google Scholar 

  63. Greenlee, C. et al. Electro-optic polymer spatial light modulator based on a Fabry–Perot interferometer configuration. Opt. Express 19, 12750–12758 (2011).

    Article  ADS  Google Scholar 

  64. Yang, W. et al. High speed optical phased array using high contrast grating all-pass filters. Opt. Express 22, 20038–20044 (2014).

    Article  ADS  Google Scholar 

  65. Wang, Y. et al. 2D broadband beamsteering with large-scale MEMS optical phased array. Optica 6, 557–562 (2019).

    Article  ADS  Google Scholar 

  66. 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).

    Article  ADS  Google Scholar 

  67. 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).

    Article  ADS  Google Scholar 

  68. 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).

    Article  Google Scholar 

  69. Wang, Q. et al. Optically reconfigurable metasurfaces and photonic devices based on phase change materials. Nat. Photon. 10, 60–65 (2016).

    Article  ADS  Google Scholar 

  70. Arbabi, E. et al. MEMS-tunable dielectric metasurface lens. Nat. Commun. 9, 812 (2018).

    Article  ADS  Google Scholar 

  71. 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).

    Article  ADS  Google Scholar 

  72. Shirmanesh, G. K., Sokhoyan, R., Wu, P. C. & Atwater, H. A. Electro-optically tunable multifunctional metasurfaces. ACS Nano 14, 6912–6920 (2020).

    Article  Google Scholar 

  73. Benea-Chelmus, I.-C. et al. Electro-optic spatial light modulator from an engineered organic layer. Nat. Commun. 12, 5928 (2021).

    Article  ADS  Google Scholar 

  74. 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).

    Article  ADS  Google Scholar 

  75. 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).

  76. 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).

    Article  ADS  Google Scholar 

  77. Ito, H. et al. Wide beam steering by slow-light waveguide gratings and a prism lens. Optica 7, 47–52 (2020).

    Article  ADS  Google Scholar 

  78. Huang, Y.-W. et al. Gate-tunable conducting oxide metasurfaces. Nano Lett. 16, 5319–5325 (2016).

    Article  ADS  Google Scholar 

  79. Shuai, Y.-C. et al. Coupled bilayer photonic crystal slab electro-optic spatial light modulators. IEEE Photon. J. 9, 7101411 (2017).

    Article  MathSciNet  Google Scholar 

  80. Ye, X. et al. High-speed programmable lithium niobate thin film spatial light modulator. Opt. Letters 46, 1037–1040 (2021).

    Article  ADS  Google Scholar 

  81. 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).

    Article  Google Scholar 

  82. Tamanuki, T., Ito, H. & Baba, T. Thermo-optic beam scanner employing silicon photonic crystal slow-light waveguides. J. Light. Technol. 39, 904–911 (2021).

    Article  ADS  Google Scholar 

  83. Sakata, R. et al. Dually modulated photonic crystals enabling high-power high-beam-quality two-dimensional beam scanning lasers. Nat. Commun. 11, 3487 (2020).

  84. Minkov, M. & Savona, V. Automated optimization of photonic crystal slab cavities. Sci. Rep. 4, 5124 (2014).

    Article  ADS  Google Scholar 

  85. Minkov, M. et al. Inverse design of photonic crystals through automatic differentiation. ACS Photonics 7, 1729–1741 (2020).

    Article  Google Scholar 

  86. 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).

    Article  ADS  Google Scholar 

  87. Panuski, C., Englund, D. & Hamerly, R. Fundamental thermal noise limits for optical microcavities. Phys. Rev. X 10, 041046 (2020).

    Google Scholar 

  88. Lie, L. N., Razouk, R. R. & Deal, B. E. High pressure oxidation of silicon in dry oxygen. J. Electrochem. Soc. 129, 2828 (1982).

    Article  ADS  Google Scholar 

  89. 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).

    Article  ADS  Google Scholar 

  90. Shaltout, A. M. et al. Spatiotemporal light control with frequency-gradient metasurfaces. Science 365, 374–377 (2019).

    Article  ADS  Google Scholar 

  91. Pahlevaninezhad, H. et al. Nano-optic endoscope for high-resolution optical coherence tomography in vivo. Nat. Photon. 12, 540–547 (2018).

    Article  ADS  Google Scholar 

  92. Watts, M. R., Shaw, M. J. & Nielson, G. N. Microphotonic thermal imaging. Nat. Photon. 1, 632–634 (2007).

    Article  ADS  Google Scholar 

  93. 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).

    Article  ADS  Google Scholar 

  94. 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).

    Article  ADS  Google Scholar 

  95. Yoon, S. et al. Deep optical imaging within complex scattering media. Nat. Rev. Phys. 2, 141–158 (2020).

    Article  Google Scholar 

  96. Bourassa, J. E. et al. Blueprint for a scalable photonic fault-tolerant quantum computer. Quantum 5, 392 (2021).

    Article  Google Scholar 

  97. Bartolucci, S. et al. Fusion-based quantum computation. Preprint at https://arxiv.org/abs/2101.09310 (2021).

  98. Heuck, M., Jacobs, K. & Englund, D. R. Controlled-phase gate using dynamically coupled cavities and optical nonlinearities. Phys. Rev. Lett. 124, 160501 (2020).

    Article  ADS  Google Scholar 

  99. Krastanov, S. et al. Room-temperature photonic logical qubits via second-order nonlinearities. Nat. Commun. 12, 191 (2021).

    Article  Google Scholar 

  100. Dostart, N. et al. Serpentine optical phased arrays for scalable integrated photonic lidar beam steering. Optica 7, 726–733 (2020).

    Article  ADS  Google Scholar 

  101. Aflatouni, F., Abiri, B., Rekhi, A. & Hajimiri, A. Nanophotonic projection system. Opt. Express 23, 21012–21022 (2015).

    Article  ADS  Google Scholar 

  102. Junique, S. et al. GaAs-based multiple-quantum-well spatial light modulators fabricated by a wafer-scale process. Appl. Opt. 44, 1635–1641 (2005).

    Article  ADS  Google Scholar 

  103. Yaacobi, A. et al. Integrated phased array for wide-angle beam steering. Opt. Lett. 39, 4575–4578 (2014).

    Article  ADS  Google Scholar 

  104. 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).

  105. 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).

  106. Li, J., Yu, P., Zhang, S. & Liu, N. Electrically-controlled digital metasurface device for light projection displays. Nat. Commun. 11, 3574 (2020).

  107. Marshel, J. H. et al. Cortical layer–specific critical dynamics triggering perception. Science 365, eaaw5202 (2019).

    Article  Google Scholar 

  108. McKnight, D. J., Johnson, K. M. & Serati, R. A. 256 × 256 liquid-crystal-on-silicon spatial light modulator. Appl. Opt. 33, 2775–2784 (1994).

    Article  ADS  Google Scholar 

  109. Jayatilleka, H. et al. Post-fabrication trimming of silicon photonic ring resonators at wafer-scale. J. Light. Technol. 39, 5083–5088 (2021).

    Article  ADS  Google Scholar 

  110. 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).

    Article  ADS  Google Scholar 

  111. 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).

    Article  ADS  Google Scholar 

  112. Han, S. & Shi, Y. Post-fabrication trimming of photonic crystal nanobeam cavities by electron beam irradiation. Opt. Express 26, 15908–15913 (2018).

    Article  ADS  Google Scholar 

  113. Gil-Santos, E. et al. Scalable high-precision tuning of photonic resonators by resonant cavity-enhanced photoelectrochemical etching. Nat. Commun. 8, 14267 (2017).

    Article  ADS  Google Scholar 

  114. 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).

    Article  ADS  Google Scholar 

  115. Lipka, T., Kiepsch, M., Trieu, H. K. & Müller, J. Hydrogenated amorphous silicon photonic device trimming by UV-irradiation. Opt. Express 22, 12122–12132 (2014).

    Article  ADS  Google Scholar 

  116. 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).

    Article  ADS  Google Scholar 

  117. Cai, T., Bose, R., Solomon, G. S. & Waks, E. Controlled coupling of photonic crystal cavities using photochromic tuning. Appl. Phys. Lett. 102, 141118 (2013).

    Article  ADS  Google Scholar 

  118. 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).

    Article  ADS  Google Scholar 

Download references

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.

Author information

Authors and Affiliations

Authors

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.

Corresponding authors

Correspondence to Christopher L. Panuski or Dirk R. Englund.

Ethics declarations

Competing interests

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.

Peer review

Peer review information

Nature Photonics thanks Subhojit Dutta, Volkan Gurses and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data

Extended Data Table 1 Performance comparison of our PhC-SLM (bold) to selected active 2D spatial light modulators from Fig. 1b. Estimated fill factors ζ are marked by a *. Wavelength-steered devices 100 are excluded to focus on active, individually-addressable arrays
Extended Data Table 2 Comparison of previous microcavity array trimming techniques to our parallel laser assisted thermal oxidation (bold). Estimated values are marked with a *. Δλp-p = peak-to-peak wavelength error; Q = mean quality factor

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.

Supplementary information

Supplementary Information

Supplementary Sections A–G, Figs. 1–8 and Table 1.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

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

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41566-022-01086-9

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing