6c, where a driving power of 16mW (corresponding peak-to-peak driving voltage, Vpp, of Vpp=2.5V) splits the cavity resonance into five with notable magnitudes (black curve), resulting in a cavity transmission with five side lobes (blue curve). Light is coupled into and out of the EOM chip via one lensed fiber. To improve the electro-optic coupling, we utilize a partially etched structure with a rib-waveguide-like cross-section (Figs. Thank you for visiting nature.com. Hybrid silicon photonic-lithium niobate electro-optic MachZehnder modulator beyond 100 GHz. and JavaScript. Femtofarad optoelectronic integration demonstrating energy-saving signal conversion and nonlinear functions. https://doi.org/10.1038/s41586-018-0551-y, Complementary Metal Oxide Semiconductor (CMOS). C.W., M.Z., X.C. Appl. Nature 435, 325327 (2005). Wang, C., Zhang, M., Stern, B., Lipson, M. & Lonar, M. Nanophotonic lithium niobate electro-optic modulators. a Recorded transmission spectrum of the EOM cavity as a function of applied DC voltage from 0 to 4.5V, with a voltage step of 0.5V. b Recorded resonance shift as a function of applied DC voltage, where the experimental data are shown in black dots and the blue line is a linear fitting to the data. 16, 18 (2018). 4, e255 (2015). Marko Lonar. https://doi.org/10.1038/s41467-020-17950-7, DOI: https://doi.org/10.1038/s41467-020-17950-7. 5 Comparison of integrated and conventional LN modulators. Express 20, 29742981 (2012). Lee, M. et al. To show this phenomenon, we applied a sinusoidal RF signal at a certain frequency to the EOM and monitored the transmission spectrum of the device by scanning laser back and forth across the cavity resonance. Lu, H. et al. 8b, c. However, Fig. 35, 346396 (2017). 9, 525528 (2015). d Recorded transmission spectra at different RF modulation frequencies varying from 0.4 to 3.0GHz, with a frequency step of 0.2GHz. This mode, however, has only negligible perturbation to the dielectric mode due to distinctive spatial symmetry, thus not affecting the quality of the defect cavity mode. 94, 241107 (2009). Miller, D. A. Nature 528, 534538 (2015). The broad modulation bandwidth of these devices would thus enable high-speed electro-optic switching. Opt. The authors thank Professor Hui Wu and Professor Wayne Knox for the use of their equipment. ac, Normalized optical transmission of the 20-mm (a), 10-mm (b) and 5-mm (c) device as a function of the applied voltage, showing half-wave voltages of 1.4V, 2.3V and 4.4V, respectively. Rao, A. et al. The laser wavelength is scanned at a repetition rate of ~15Hz, so we primarily monitored the time-averaged cavity transmission. Google Scholar. Ultrahigh-Q lithium niobate microring resonator with multimode waveguide Nat. Figure2 shows a fabricated device (see Methods for the details of device fabrication). Chen, L., Wood, M. G. & Reano, R. M. 12.5 pm/V hybrid silicon and lithium niobate optical microring resonator with integrated electrodes. Marpaung, D., Yao, J. To show this feature, we selected another similar device on the same chip, which has a lower loaded optical Q of 14,000. In 2015 IEEE Compound Semiconductor Integrated Circuit Symposium 14 (2015); https://doi.org/10.1109/CSICS.2015.7314513, Letal, G. et al. Article Tzuang, L. D., Fang, K., Nussenzveig, P., Fan, S. & Lipson, M. Non-reciprocal phase shift induced by an effective magnetic flux for light. The data sets generated and/or analysed during the current study are available from the corresponding authors on reasonable request. Kues, M. et al. Input Requirements LiNbO 3 Its a building block that can be integrated into larger optical systems for a range of applications, in sensing, lidar, and data telecommunications.. Deep learning with coherent nanophotonic circuits. Full Text electro optic modulator 10.1109/LPT.2021.3056913. ADS The cavity resonance exhibits a coupling depth of 93%, corresponding to a full-swing extinction ratio of 11.5dB. A 10-Gbit/s lithium niobate intensity module provides chirp-free modulation at 1550 nm. In the past decade, photonic-crystal EOMs have been developed on various material platforms such as silicon32,33,34, GaAs35, InP36, polymers37,38, ITO39, etc. CAS The left inset shows the orientation of the LN crystal where the optical axis is along the z direction. Optica 1, 112118 (2014). Lithium Niobate Electro-Optic Modulators. Micro-transfer printing of thin-film lithium niobate offers a solution, but suspending large areas of thin films for long interaction lengths and high-Q resonators is challenging, resulting in a low transfer . Zhang, M., Wang, C., Cheng, R., Shams-Ansari, A. 7a. Publishers note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. As the modulation bandwidth is primarily related to the optical Q of the device, it can be engineered flexibly for different application purposes, simply by choosing device with appropriate optical Q. High performance optical modulator based on electro-optic polymer filled silicon slot photonic crystal waveguide. The electro-optic modulation demonstrated in the previous section indicates the potential high-speed operation of the EOMs. High-speed Femto-Joule per bit silicon-conductive oxide nanocavity modulator. Karpiski, M., Jachura, M., Wright, L. J. Quantum Electron. Nat. The current generation of lithium niobate modulators are bulky, expensive, limited in bandwidth and require high drive voltages, and thus are unable to reach the full potential of the material. How Lithium Niobate Modulator Helps in Meeting Telecommunication Needs b Same as a but with a modulation frequency of 2.0GHz. Li, M., Liang, H., Luo, R., He, Y. Recently, thin-film lithium niobate (LN) emerges as a promising platform for photonic integrated circuits. Electro-optic modulation in slotted resonant photonic crystal heterostructures. 100G/400G LN Modulator. Our thin-film modulator (a) has an oxide layer underneath the device layer, so that velocity matching can be achieved while maximum electro-optic efficiency is maintained. 27 March 2023, Receive 51 print issues and online access, Get just this article for as long as you need it, Prices may be subject to local taxes which are calculated during checkout. The modulators enable efficient electro-optic driving of high-Q photonic cavity modes in both adiabatic and non-adiabatic regimes, and allow us to achieve electro-optic switching at 11 Gb s1 with a bit-switching energy as low as 22 fJ. & Thomson, D. J. A. The fully on-chip design achieves a full-swing extinction ratio of 11.5dB. The extinction ratio can be significantly improved by further optimization of the photonic-crystal mirrors (Fig. P.W. Wang, J. et al. Nat. The gray curves show the created individual sidebands with Lorentzian-shape resonances and the dashed vertical lines indicates their relative frequency positions. It, however, degrades considerably the optical Q of the cavity (Fig. Lithium niobate modulator | Laser Focus World Haffner, C. et al. Miller, D. A. That highlighted in blue indicates the large metal pad used for contacting the RF probe. CAS To date, it remains an open challenge in realizing a high-speed and energy-efficient modulator at the wavelength scale on the monolithic LN platform. For all the recent advances in integrated lithium niobate photonic circuits from frequency combs to frequency converters and modulators one big component has remained frustratingly difficult to integrate: lasers. Express 26, 15471555 (2018). Express 20, 2246522474 (2012). Google Scholar. Integrated microwave photonics. Wang, C. et al. This work is supported in part by the National Science Foundation (NSF) (ECCS1609549, ECCS-1740296 E2CDA and DMR-1231319) and by Harvard University Office of Technology Development (Physical Sciences and Engineering Accelerator Award). Photon. Weigel, P. O. et al. Quant. Configuration of the FDTD simulation. The 0.8 m lithium niobate layer Folded Heterogeneous Silicon and Lithium Niobate Mach-Zehnder - MDPI Opt. They also thank Wuxiucheng Wang, Lejie Lu, and Ming Gong for valuable discussions and help on testing. B. Attojoule optoelectronics for low-energy information processing and communications. Open Access articles citing this article. J. Lightwave Technol. Google Scholar. First integrated laser on lithium niobate chip - Harvard John A Photon. 8b), which, however, might sacrifice the optical Q due to metallic losses. Integrating high-performance plug-and-play lasers would significantly reduce the cost, complexity, and power consumption of future communication systems, said Amirhassan Shams-Ansari, a graduate student at SEAS and first author of the study. With these devices, we are able to demonstrate efficient electrical driving of high-Q cavity mode in both adiabatic and non-adiabatic regimes and to observe transition in between. Sign up for the Nature Briefing newsletter what matters in science, free to your inbox daily. Boyd, R. W. Nonlinear Optics (Academic, Cambridge, 2003). Among various device geometries, photonic-crystal nanoresonators are particularly beneficial in this regard, given their exceptional capability of controlling light confinement and lightmatter interactions on the sub-wavelength scale. Velocity matching can be achieved with an oxide thickness of about 4,700nm. It was supported by the Defense Advanced Research Projects Agency under grant HR0011-20-C-0137 and the Air Force Office of Scientific Research under grant FA9550-19-1-0376. Opt. Photonics 13, 359364 (2019). Here, we fabricate a multimode microring resonator with an intrinsic Q of 6 106, which exhibits a propagation loss 50 times lower than that of a single-mode LN microring fabricated under the same process. and M.L. Appl. The modulator is designed to be used in externally modulated fiberoptic transmitters for supertrunking of digitized cable-TV signals as well as for long-haul transmission of OC-192 data. Express 21, 3035030357 (2013). Wooten, E. L. et al. Mercante, A. J. et al. Winzer, P. J. Appl. a, Set-up for measuring the modulator electro-optic responses from 35GHz to 100GHz. Lithium niobate photonic-crystal electro-optic modulator The 50-m width of the electrode (Fig. High-performance and linear thin-film lithium niobate Mach-Zehnder modulators on silicon up to 50 GHz. Such a configuration reduces the critical requirement of electrode alignment as needed in . When the modulation frequency is below 1.0GHz, The transmission spectrum remains fairly similar regardless of modulation frequency, as expected from the adiabatic driving discussed above. The modulators are manufactured upon a commercial x-cut lithium niobate on isolator (LNOI) wafer (NANOLN) with a thin-film LN thickness of 500 nm, which is bonded to a buried silica (SiO 2) layer on a 500-m-thick silicon (Si) substrate. b, c Electro-optic tuning efficiency and optical quality factor of the device as a function of Gap and tw, simulated by the FEM method. 3). All of these applications require chip-scale electro-optic modulators that operate at voltages compatible with complementary metaloxidesemiconductor (CMOS) technology, have ultra-high electro-optic bandwidths and feature very low optical losses. High-quality lithium niobate photonic crystal nanocavities. Department of Electrical and Computer Engineering, University of Rochester, Rochester, NY, 14627, USA, Mingxiao Li,Jingwei Ling,Yang He&Qiang Lin, Institute of Optics, University of Rochester, Rochester, NY, 14627, USA, You can also search for this author in C.W. supervised the project. The orange curve in Fig. We used two cascaded travelling wave phase modulators for spatiotemporal modulation and a racetrack resonator as a wavelength filter to suppress the sidebands of the reverse propagating . ISSN 0028-0836 (print). Ghelfi, P. et al. Power efficiency is crucial for the application of electro-optic modulator (EOM), which depends sensitively on the physical size of the device27. Electro-optic modulation using lithium niobate metasurfaces with For simplicity of testing, the EOM is designed such that light is coupled into and out of the EOM via only one side of the cavity (Fig. A variety of approaches have been employed for electro-optic modulation, such as carrier plasma dispersion6,7, electro-absorption8,9, and Pockels effect1,10, the latter of which is particularly interesting since the Pockels effect offers an ultrafast and pure refractive-index modulation over an extremely broad optical spectrum while without introducing extra loss. Google Scholar. Appl. Nature 562, 101104 (2018). Fortier, T. M. et al. By placing the metal electrodes on top and bottom of the waveguide rather than the usual lateral configuration, the electric field is fully overlapping the optical field. Although the breaking of the mirror symmetry along the normal direction of the device plane considerably alters the band gap of the photonic crystal (Fig. The insertion loss from the on-chip coupling waveguide to the photonic-crystal cavity is measured to be around 2.2dB, calibrated by subtracting the facet coupling and circulator transmission loss. Di Zhu, and Mengjie Yu, from SEAS, Hannah R. Grant, Leif Johansson from Freedom Photonics and Lingyan He and Mian Zhang from HyperLight Corporation. Electro-optic modulation enables arbitrary modulation of cavity resonance within the bandwidth allowed by the driving circuit. Thin-film lithium niobate (TFLN) has emerged via recent progress in fabrication [20, 21] as a photonics platform with a unique set of capabilities for high-speed applications [22,23,24].While bulk and diffuse-waveguide LN have long been the workhorses of telecommunication technologies, TFLN waveguides offer nanometer-scale confinement, reducing device size, nonlinear thresholds, and switching . Boes, A., Corcoran, B., Chang, L., Bowers, J. In 2017 Optical Fiber Communications Conference and Exhibition 13 (2017); https://doi.org/10.1364/OFC.2017.Tu2H.7. Correspondence to Photon. Low power 50Gb/s silicon traveling wave MachZehnder modulator near 1300nm. We are also able to achieve high-speed electro-optic switching of at 11Gbs1, with switching energy as low as 22fJ per bit. Nature Increasing the electrical driving power now does not perturb the positions of the resonance dips, but rather changes their relative magnitudes since the magnitudes of the created sidebands depends on the driving amplitude48. Opt. Femtojoule electro-optic modulation using a silicon-organic hybrid device. The blue column shows another design with broader bandwidth and enhanced electro-optic coupling. On chip, the lasers sit in small wells or trenches etched into the lithium niobate and deliver up to 60 milliwatts of optical power in the waveguides fabricated in the same platform. Introduction to Lithium Niobate - Academic Accelerator Express 24, 1559015595 (2016). 34, 29412951 (2016). As shown in Fig. 11, 441446 (2017). NTT Tech. Phys. J. Lightwave Technol. has protected the intellectual property arising from the Loncar Labs innovations in lithium niobate systems. b Zoom-in image of the photonic-crystal resonator and electrodes, corresponding to the dashed rectangular region in a. c Further zoom-in image showing the detailed structure of the photonic-crystal defects cavity, corresponding to the dashed rectangular region in b. Near-field enhancement of optical second harmonic generation in hybrid Electro-optically (EO) tunable metasurfaces have received considerable attention owing to their capability for dynamic light field control. As shown in Fig. b Detailed transmission spectrum of the fundamental TE-like cavity mode \({\mathrm{{TE}}}_{01}^{0}\) at a wavelength of 1554.47nm, with the experimental data shown in blue and the theoretical fitting shown in red. 101, 151117 (2012). The cavity mode exhibits an extremely small electro-optic modal volume of 1.52(/n)3~0.58m3 (where n is the refractive index of LN). 5 implies that the linearity of electro-optic modulation in the devices would reach the intrinsic limit determined by the fundamental Lorentzian shape of the cavity resonance47. CAS 1a) since it supports compact optical and electrical integration to enhance the electro-optic response. Slider with three articles shown per slide. Rao, A. 1d and8a). Silicon optical modulators. The inset shows an optical microscopic image of an EOM with the RF probe in contact. If material is not included in the articles Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. Opt. Further increase of the modulation frequency shifts apart the two side lobes accordingly, with amplitude decreased, while the position of the center lobe remains unchanged, as expected from the non-adiabatic driving. Phys. http://www.fujitsu.com/jp/group/foc/en/products/optical-devices/100gln/, Eospace 2017 Advanced Products. Light Sci. Extended Data Fig. Lithium niobate optical modulators: Devices and applications Wlbern, J. H. et al. After the residue removal, we used diluted hydrofluoric acid to undercut the buried oxide layer to form a suspended photonic-crystal membrane structure (Fig. Provided by the Springer Nature SharedIt content-sharing initiative. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate. Electron. C.W., M.Z., X.C., P.W. Lett. Google Scholar. Opt. For the application of high-speed electro-optic switching, our simulations show that the electrode-waveguide spacing can be decreased to 1.5m for an optical Q of ~5000 (corresponding to a modulation bandwidth of ~45GHz), which will improve the modulation efficiency to 2.38GHzV1 (simulation details in Methods). Here we report high-speed and energy-efficient LN photonic-crystal EOMs, which exhibits a tiny electro-optic modal volume of only ~0.58m3, the smallest among all high-speed LN EOMs ever reported1,13,14,15,16,17,18,19,20,21,22,23,24,25,26, to the best of our knowledge. [29] Owing to the disparity between the dielectric constants of lithium niobate and silica, the electrical field primarily affected the LN core through the slab. HDTRA11810047); and the Defense Advanced Research Projects Agency (DARPA) under Agreement No. Such flexibility allows us to observe direct transition between the adiabatic driving regime and the non-adiabatic regime simply by continuously sweeping the modulation frequency to across the cavity linewidth. This is a preview of subscription content, access via your institution. conceived the experiment. Essentially, only the 10-m long point-defect cavity requires electric driving to achieve electro-optic modulation. Input requirements, test setups, and mounting instructions will be covered.