[1] P. A. Franken, A. E. Hill, C. W. Peters, G. Weinreich. Generation of optical harmonics. Phys. Rev. Lett., 7, 118(1961).
[2] L. P. Gonzalez, D. C. Upchurch, P. G. Schunemann, L. Mohnkern, S. Guha. Second-harmonic generation of a tunable continuous-wave CO2 laser in orientation-patterned GaAs. Opt. Lett., 38, 320(2013).
[3] Y. Liu, X. Yan, J. Wu, B. Zhu, Y. Chen, X. Chen. On-chip erbium-doped lithium niobate microcavity laser. Sci. Chin. Phys. Mech. Astron., 64, 234262(2020).
[4] S. V. Makarov, M. I. Petrov, U. Zywietz, V. Milichko, D. Zuev, N. Lopanitsyna, A. Kuksin, I. Mukhin, G. Zograf, E. Ubyivovk, D. A. Smirnova, S. Starikov, B. N. Chichkov, Y. S. Kivshar. Efficient second-harmonic generation in nanocrystalline silicon nanoparticles. Nano Lett., 17, 3047(2017).
[5] Y. Qiao, Y. Peng, Y. Zheng, F. Ye, X. Chen. Second-harmonic focusing by a nonlinear turbid medium via feedback-based wavefront shaping. Opt. Lett., 42, 1895(2017).
[6] M. Yu, L. Shao, Y. Okawachi, A. L. Gaeta, M. Loncar. Ultraviolet to mid-infrared supercontinuum generation in lithium-niobate waveguides. CLEO: Science and Innovations, STu4H. 1(2020).
[7] M. Yu, B. Desiatov, Y. Okawachi, A. L. Gaeta, M. Lončar. Coherent two-octave-spanning supercontinuum generation in lithium-niobate waveguides. Opt. Lett., 44, 1222(2019).
[8] A. Sergeyev, R. Geiss, A. S. Solntsev, A. Steinbruck, F. Schrempel, E. B. Kley, T. Pertsch, R. Grange. Second-harmonic generation in lithium niobate nanowires for local fluorescence excitation. Opt. Express, 21, 19012(2013).
[9] N. C. Panoiu, W. E. I. Sha, D. Y. Lei, G. C. Li. Nonlinear optics in plasmonic nanostructures. J. Opt., 20, 083001(2018).
[10] B. Zhang, L. Wang, F. Chen. Recent advances in femtosecond laser processing of LiNbO3 crystals for photonic applications. Laser Photon. Rev., 14, 1900407(2020).
[11] B. Sain, C. Meier, T. Zentgraf. “Nonlinear optics in all-dielectric nanoantennas and metasurfaces: a review. Adv. Photon., 1, 024002(2019).
[12] H. Lu, H. Xiong, Z. Huang, Y. Li, H. Dong, D. He, J. Dong, H. Guan, W. Qiu, X. Zhang, W. Zhu, J. Yu, Y. Luo, J. Zhang, Z. Chen. Electron-plasmon interaction on lithium niobate with gold nanolayer and its field distribution dependent modulation. Opt. Express, 27, 19852(2019).
[13] A. Rao, S. Fathpour. Heterogeneous thin-film lithium niobate integrated photonics for electrooptics and nonlinear optics. IEEE J. Sel. Top. Quantum Electron., 24, 8200912(2018).
[14] C. Pang, R. Li, Z. Li, N. Dong, F. Ren, J. Wang, F. Chen. A novel hierarchical nanostructure for enhanced optical nonlinearity based on scattering mechanism. Small, 16, 2003172(2020).
[15] Y. Jia, L. Wang, F. Chen. Ion-cut lithium niobate on insulator technology: recent advances and perspectives. Appl. Phys. Rev., 8, 011307(2021).
[16] M. Levy, R. M. Osgood, R. Liu, L. E. Cross, G. S. Cargill, A. Kumar, H. Bakhru. Fabrication of single-crystal lithium niobate films by crystal ion slicing. Appl. Phys. Lett., 73, 2293(1998).
[17] A. Honardoost, K. Abdelsalam, S. Fathpour. Rejuvenating a versatile photonic material: thin‐film lithium niobate. Laser Photon. Rev., 14, 2000088(2020).
[18] P. Rabiei, P. Gunter. Optical and electro-optical properties of submicrometer lithium niobate slab waveguides prepared by crystal ion slicing and wafer bonding. Appl. Phys. Lett., 85, 4603(2004).
[19] B. Zhu, H. Liu, Y. A. Liu, X. Yan, Y. Chen, X. Chen. Second-harmonic computer-generated holographic imaging through monolithic lithium niobate crystal by femtosecond laser micromachining. Opt. Lett., 45, 4132(2020).
[20] G. T. Reed, G. Z. Mashanovich, F. Y. Gardes, M. Nedeljkovic, Y. Hu, D. J. Thomson, K. Li, P. R. Wilson, S.-W. Chen, S. S. Hsu. Recent breakthroughs in carrier depletion based silicon optical modulators. Nanophotonics, 3, 229(2014).
[21] J.-Y. Chen, Y. M. Sua, Z.-H. Ma, C. Tang, Z. Li, Y.-P. Huang. Efficient parametric frequency conversion in lithium niobate nanophotonic chips. OSA Continuum, 2, 2914(2019).
[22] L. Chang, Y. Li, N. Volet, L. Wang, J. Peters, J. E. Bowers. Thin film wavelength converters for photonic integrated circuits. Optica, 3, 531(2016).
[23] T. J. Kippenberg, R. Holzwarth, S. A. Diddams. Microresonator-based optical frequency combs. Science, 332, 555(2011).
[24] Z. Huang, H. Lu, H. Xiong, Y. Li, H. Chen, W. Qiu, H. Guan, J. Dong, W. Zhu, J. Yu, Y. Luo, J. Zhang, Z. Chen. Fano resonance on nanostructured lithium niobate for highly efficient and tunable second harmonic generation. Nanomaterials, 9, 69(2019).
[25] D. Smirnova, A. I. Smirnov, Y. S. Kivshar. Multipolar second-harmonic generation by Mie-resonant dielectric nanoparticles. Phys. Rev. A, 97, 013807(2018).
[26] N. Yao, J. Zhou, R. Gao, J. Lin, M. Wang, Y. Cheng, W. Fang, L. Tong. Efficient light coupling between an ultra-low loss lithium niobate waveguide and an adiabatically tapered single mode optical fiber. Opt. Express, 28, 12416(2020).
[27] J. Lin, F. Bo, Y. Cheng, J. Xu. Advances in on-chip photonic devices based on lithium niobate on insulator. Photon. Res., 8, 1910(2020).
[28] M. Bazzan, C. Sada. Optical waveguides in lithium niobate: recent developments and applications. Appl. Phys. Rev., 2, 040603(2015).
[29] W. J. Park, W. S. Yang, W. K. Kim, H. Y. Lee, J. W. Lim, M. Isshiki, D. H. Yoon. Ridge structure etching of LiNbO3 crystal for optical waveguide applications. Opt. Mater., 28, 216(2006).
[30] R. Wolf, I. Breunig, H. Zappe, K. Buse. Cascaded second-order optical nonlinearities in on-chip micro rings. Opt. Express, 25, 29927(2017).
[31] L. Arizmendi. Photonic applications of lithium niobate crystals. Phys. Status Solidi (A), 201, 253(2004).
[32] R. W. Boyd. Nonlinear Optics(2003).
[33] S. Fathpour. Heterogeneous nonlinear integrated photonics. IEEE J. Quantum Electron., 54, 6300716(2018).
[34] J. A. Armstrong, N. Bloembergen, J. Ducuing, P. S. Pershan. Interactions between light waves in a nonlinear dielectric. Phys. Rev., 127, 1918(1962).
[35] J. E. Toney. Lithium Niobate Photonics(2015).
[36] L. Cai, Y. Wang, H. Hu. Efficient second harmonic generation in χ(2) profile reconfigured lithium niobate thin film. Opt. Commun., 387, 405(2017).
[37] J. Webjörn, D. Nam, S. Siala, R. Waarts. Nonlinear waveguides on the way to the marketplace. Opt. Photon. News, 8, 16(1997).
[38] Y. Qi, Y. Li. Integrated lithium niobate photonics. Nanophotonics, 9, 1287(2020).
[39] C. Wang, C. Langrock, A. Marandi, M. Jankowski, M. Zhang, B. Desiatov, M. M. Fejer, M. Lončar. Ultrahigh-efficiency wavelength conversion in nanophotonic periodically poled lithium niobate waveguides. Optica, 5, 1438(2018).
[40] Y. Niu, C. Lin, X. Liu, Y. Chen, X. Hu, Y. Zhang, X. Cai, Y.-X. Gong, Z. Xie, S. Zhu. Optimizing the efficiency of a periodically poled LNOI waveguide using in situ monitoring of the ferroelectric domains. Appl. Phys. Lett., 116, 101104(2020).
[41] T. Ding, Y. Zheng, X. Chen. Integration of cascaded electro-optic and nonlinear processes on a lithium niobate on insulator chip. Opt. Lett., 44, 1524(2019).
[42] J. Zhao, M. Rüsing, U. A. Javid, J. Ling, M. Li, Q. Lin, S. Mookherjea. Shallow-etched thin-film lithium niobate waveguides for highly-efficient second-harmonic generation. Opt. Express, 28, 19669(2020).
[43] L. Wang, L.-Q. Li, X.-T. Zhang, F. Chen. Type I phase matching in thin film of lithium niobate on insulator. Res. Phys., 16, 103011(2020).
[44] C. Wang, X. Xiong, N. Andrade, V. Venkataraman, X.-F. Ren, G.-C. Guo, M. Lončar. Second harmonic generation in nano-structured thin-film lithium niobate waveguides. Opt. Express, 25, 6963(2017).
[45] A. Rao, J. Chiles, S. Khan, S. Toroghi, M. Malinowski, G. F. Camacho-González, S. Fathpour. Second-harmonic generation in single-mode integrated waveguides based on mode-shape modulation. Appl. Phys. Lett., 110, 111109(2017).
[46] J. Lu, J. B. Surya, X. Liu, A. W. Bruch, Z. Gong, Y. Xu, H. X. Tang. Periodically poled thin-film lithium niobate microring resonators with a second-harmonic generation efficiency of 250,000%/W. Optica, 6, 1455(2019).
[47] C. Wang, Z. Li, M.-H. Kim, X. Xiong, X.-F. Ren, G.-C. Guo, N. Yu, M. Lončar. Metasurface-assisted phase-matching-free second harmonic generation in lithium niobate waveguides. Nat. Commun., 8, 2098(2017).
[48] B. Fang, H. Li, S. Zhu, T. Li. Second-harmonic generation and manipulation in lithium niobate slab waveguides by grating metasurfaces. Photon. Res., 8, 1296(2020).
[49] L. Zhang, Z. Hao, W. Mao, A. Gao, F. Bo, F. Gao, G. Zhang, J. Xu. Biperiodically poled lithium niobate microcavities for multiple nonlinear optical processes. CLEO: Science and Innovations, JTh2E.17(2020).
[50] Y. Qiao, F. Ye, Y. Zheng, X. Chen. Cavity-enhanced second-harmonic generation in strongly scattering nonlinear media. Phys. Rev. A, 99, 043844(2019).
[51] F. Timpu, J. Sendra, C. Renaut, L. Lang, M. Timofeeva, M. T. Buscaglia, V. Buscaglia, R. Grange. Lithium niobate nanocubes as linear and nonlinear ultraviolet Mie resonators. ACS Photon., 6, 545(2019).
[52] A. Fedotova, M. Younesi, J. Sautter, A. Vaskin, F. J. F. Löchner, M. Steinert, R. Geiss, T. Pertsch, I. Staude, F. Setzpfandt. Second-harmonic generation in resonant nonlinear metasurfaces based on lithium niobate. Nano Lett., 20, 8608(2020).
[53] J. Ma, M. Ren, W. Wu, W. Cai, J. Xu. Resonantly tunable second harmonic generation from lithium niobate metasurfaces(2020).
[54] V. F. Gili, L. Ghirardini, D. Rocco, G. Marino, I. Favero, I. Roland, G. Pellegrini, L. Duò, M. Finazzi, L. Carletti, A. Locatelli, A. Lemaître, D. Neshev, C. De Angelis, G. Leo, M. Celebrano. Metal–dielectric hybrid nanoantennas for efficient frequency conversion at the anapole mode. Beilstein J. Nanotechnol., 9, 2306(2018).
[55] G. Grinblat, M. Rahmani, E. Cortés, M. Caldarola, D. Comedi, S. A. Maier, A. V. Bragas. High-efficiency second harmonic generation from a single hybrid ZnO nanowire/Au plasmonic nano-oligomer. Nano Lett., 14, 6660(2014).
[56] M. Mayy, G. Zhu, A. Webb, H. Ferguson, T. Norris, V. Podolskiy, M. Noginov. Toward parametric amplification in plasmonic systems: second harmonic generation enhanced by surface plasmon polaritons. Opt. Express, 22, 7773(2014).
[57] B. Metzger, M. Hentschel, M. Lippitz, H. Giessen. Third-harmonic spectroscopy and modeling of the nonlinear response of plasmonic nanoantennas. Opt. Lett., 37, 4741(2012).
[58] D. Bar-Lev, J. Scheuer. Efficient second harmonic generation using nonlinear substrates patterned by nano-antenna arrays. Opt. Express, 21, 29165(2013).
[59] D. Lehr, J. Reinhold, I. Thiele, H. Hartung, K. Dietrich, C. Menzel, T. Pertsch, E.-B. Kley, A. Tünnermann. Enhancing second harmonic generation in gold nanoring resonators filled with lithium niobate. Nano Lett., 15, 1025(2015).
[60] F. Lu, T. Li, X. Hu, Q. Cheng, S. Zhu, Y. Zhu. Efficient second-harmonic generation in nonlinear plasmonic waveguide. Opt. Lett., 36, 3371(2011).
[61] R. Geiss, S. Saravi, A. Sergeyev, S. Diziain, F. Setzpfandt, F. Schrempel, R. Grange, E.-B. Kley, A. Tünnermann, T. Pertsch. Fabrication of nanoscale lithium niobate waveguides for second-harmonic generation. Opt. Lett., 40, 2715(2015).
[62] L. Ai, L. Wang, Y. Tan, S. Akhmadaliev, S. Zhou, F. Chen. Efficient second harmonic generation of diced ridge waveguides based on carbon ion-irradiated periodically poled LiNbO3. J. Lightwave Technol., 35, 2476(2016).
[63] A. Rao, K. Abdelsalam, T. Sjaardema, G. F. Camacho-González, A. Honardoost, S. Fathpour. Highly efficient nonlinear integrated photonics in ultracompact periodically-poled lithium niobate on silicon. Frontiers in Optics/Laser Science, JTu3A.59(2018).
[64] R. Luo, Y. He, H. Liang, M. Li, Q. Lin. Highly tunable efficient second-harmonic generation in a lithium niobate nanophotonic waveguide. Optica, 5, 1006(2018).
[65] A. Rao, K. Abdelsalam, T. Sjaardema, A. Honardoost, G. F. Camacho-Gonzalez, S. Fathpour. Actively-monitored periodic-poling in thin-film lithium niobate photonic waveguides with ultrahigh nonlinear conversion efficiency of 4600 % W−1 cm−2. Opt. Express, 27, 25920(2019).
[66] J.-Y. Chen, C. Tang, Z.-H. Ma, Z. Li, Y. M. Sua, Y.-P. Huang. Efficient and highly tunable second-harmonic generation in Z-cut periodically poled lithium niobate nanowaveguides. Opt. Lett., 45, 3789(2020).
[67] J. Zhao, C. Ma, M. Rüsing, S. Mookherjea. High quality entangled photon pair generation in periodically poled thin-film lithium niobate waveguides. Phys. Rev. Lett., 124, 163603(2020).
[68] B. Zhang, L. Li, L. Wang, F. Chen. Second harmonic generation in femtosecond laser written lithium niobate waveguides based on birefringent phase matching. Opt. Mater., 107, 110075(2020).
[69] M. Jankowski, C. Langrock, B. Desiatov, A. Marandi, C. Wang, M. Zhang, C. R. Phillips, M. Lončar, M. M. Fejer. Ultrabroadband nonlinear optics in nanophotonic periodically poled lithium niobate waveguides. Optica, 7, 40(2020).
[70] V. Ng, A. M. Warrier, J. Lin, D. J. Spence, J. E. Downes, D. W. Coutts, J. M. Dawes. Plasmonic second-harmonic generation in gold:lithium niobate thin films. J. Opt. Soc. Am. B, 35, 302(2018).
[71] J. Zhang, Z. Fang, J. Lin, J. Zhou, M. Wang, R. Wu, R. Gao, Y. Cheng. Fabrication of crystalline microresonators of high quality factors with a controllable wedge angle on lithium niobate on insulator. Nanomaterials, 9, 1218(2019).
[72] J. Lin, Y. Xu, Z. Fang, M. Wang, J. Song, N. Wang, L. Qiao, W. Fang, Y. Cheng. Fabrication of high-Q lithium niobate microresonators using femtosecond laser micromachining. Sci. Rep., 5, 8072(2015).
[73] J. Lin, Y. Xu, J. Ni, M. Wang, Z. Fang, L. Qiao, W. Fang, Y. Cheng. Phase-matched second-harmonic generation in an on-chip LiNbO3 microresonator. Phys. Rev. Appl., 6, 014002(2016).
[74] Z. Hao, L. Zhang, A. Gao, W. Mao, X. Lyu, X. Gao, F. Bo, F. Gao, G. Zhang, J. Xu. Periodically poled lithium niobate whispering gallery mode microcavities on a chip. Sci. Chin. Phys. Mech. Astron., 61, 114211(2018).
[75] R. Luo, H. Jiang, S. Rogers, H. Liang, Y. He, Q. Lin. On-chip second-harmonic generation and broadband parametric down-conversion in a lithium niobate microresonator. Opt. Express, 25, 24531(2017).
[76] J. Lin, Y. Xu, Z. Fang, M. Wang, N. Wang, L. Qiao, W. Fang, Y. Cheng. Second harmonic generation in a high-Q lithium niobate microresonator fabricated by femtosecond laser micromachining. Sci. Chin. Phys. Mech. Astron., 58, 114209(2015).
[77] M. Wang, N. Yao, R. Wu, Z. Fang, S. Lv, J. Zhang, J. Lin, W. Fang, Y. Cheng. Strong nonlinear optics in on-chip coupled lithium niobate microdisk photonic molecules. New J. Phys., 22, 073030(2020).
[78] J. Lin, N. Yao, Z. Hao, J. Zhang, W. Mao, M. Wang, W. Chu, R. Wu, Z. Fang, L. Qiao, W. Fang, F. Bo, Y. Cheng. Broadband quasi-phase-matched harmonic generation in an on-chip monocrystalline lithium niobate microdisk resonator. Phys. Rev. Lett., 122, 173903(2019).
[79] M. Timofeeva, L. Lang, F. Timpu, C. Renaut, A. Bouravleuv, I. Shtrom, G. Cirlin, R. Grange. Anapoles in free-standing III–V nanodisks enhancing second-harmonic generation. Nano Lett., 18, 3695(2018).
[80] K. V. Baryshnikova, D. A. Smirnova, B. S. Luk’yanchuk, Y. S. Kivshar. Optical anapoles: concepts and applications. Adv. Opt. Mater., 7, 1801350(2019).
[81] K.-H. Kim, W.-S. Rim. Anapole resonances facilitated by high-index contrast between substrate and dielectric nanodisk enhance vacuum ultraviolet generation. ACS Photon., 5, 4769(2018).
[82] Y. Li, Z. Huang, Z. Sui, H. Chen, X. Zhang, W. Huang, H. Guan, W. Qiu, J. Dong, W. Zhu, J. Yu, H. Lu, Z. Chen. Optical anapole mode in nanostructured lithium niobate for enhancing second harmonic generation. Nanophotonics, 9, 3575(2020).
[83] E. Barakat, M.-P. Bernal, F. I. Baida. Doubly resonant Ag–LiNbO3 embedded coaxial nanostructure for high second-order nonlinear conversion. J. Opt. Soc. Am. B, 30, 1975(2013).
[84] E. Barakat, M.-P. Bernal, F. I. Baida. Theoretical analysis of enhanced nonlinear conversion from metallo-dielectric nano-structures. Opt. Express, 20, 16258(2012).
[85] C. Wang, M. J. Burek, Z. Lin, H. A. Atikian, V. Venkataraman, I. C. Huang, P. Stark, M. Lončar. Integrated high quality factor lithium niobate microdisk resonators. Opt. Express, 22, 30924(2014).
[86] J. Ma, J. Chen, M. Ren, W. Wu, W. Cai, J. Xu. Second-harmonic generation and its nonlinear depolarization from lithium niobate thin films. Opt. Lett., 45, 145(2020).
[87] R. Gao, H. Zhang, F. Bo, W. Fang, Z. Hao, N. Yao, J. Lin, J. Guan, L. Deng, M. Wang. Ultrahigh quality-factor microresonators fabricated in pristine lithium niobate thin film for efficient nonlinear optics applications(2021).
[88] J. Ma, F. Xie, W. Chen, J. Chen, W. Wu, W. Liu, Y. Chen, W. Cai, M. Ren, J. Xu. Nonlinear lithium niobate metasurfaces for second harmonic generation. Laser Photon. Rev., 20, 8608(2021).