[1] Hafez H A, Chai X, Ibrahim A, et al. Intense terahertz radiation and their applications[J]. Journal of Optics, 2016, 18(9): 093004.

[2] Dhillon S S, Vitiello M S, Linfield E H, et al. The 2017 terahertz science and technology roadmap[J]. Journal of Physics D: Applied Physics, 2017, 50(4): 043001.

[3] Wu X J, Calendron A L, Ravi K, et al. Optical generation of single-cycle 10 MW peak power 100 GHz waves[J]. Optics Express, 2016, 24(18): 21059-21069.

[4] Hoffmann M C, Brandt N C, Hwang H Y, et al. Terahertz Kerr effect[J]. Applied Physics Letters, 2009, 95(23): 231105.

[5] Sharma G, Razzari L, Su F H, et al. Time-resolved terahertz spectroscopy of free carrier nonlinear dynamics in semiconductors[J]. IEEE Photonics Journal, 2010, 2(4): 578-592.

[6] Fleischer S, Zhou Y, Field R W, et al. Molecular orientation and alignment by intense single-cycle THz pulses[J]. Physical Review Letters, 2011, 107(16): 163603.

[7] Tanaka K, Hirori H, Nagai M. THz nonlinear spectroscopy of solids[J]. IEEE Transactions on Terahertz Science and Technology, 2011, 1(1): 301-312.

[8] Liu M K, Hwang H Y, Tao H, et al. Terahertz-field-induced insulator-to-metal transition in vanadium dioxide metamaterial[J]. Nature, 2012, 487(7407): 345-348.

[9] Kampfrath T, Tanaka K, Nelson K A. Resonant and nonresonant control over matter and light by intense terahertz transients[J]. Nature Photonics, 2013, 7(9): 680-690.

[10] Lange C, Maag T, Hohenleutner M, et al. Extremely nonperturbative nonlinearities in GaAs driven by atomically strong terahertz fields in gold metamaterials[J]. Physical Review Letters, 2014, 113(22): 227401.

[11] Schubert O, Hohenleutner M, Langer F, et al. Sub-cycle control of terahertz high-harmonic generation by dynamical Bloch oscillations[J]. Nature Photonics, 2014, 8(8): 119-123.

[12] Egodapitiya K N, Li S, Jones R R. Terahertz-induced field-free orientation of rotationally excited molecules[J]. Physical Review Letters, 2014, 112(10): 103002.

[13] Maag T, Bayer A, Baierl S, et al. Coherent cyclotron motion beyond Kohn's theorem[J]. Nature Physics, 2016, 12(2): 119-123.

[14] Iwaszczuk K, Zalkovskij M, Strikwerda A C, et al. Nitrogen plasma formation through terahertz-induced ultrafast electron field emission[J]. Optica, 2015, 2(2): 116-123.

[15] Bahk Y M, Kang B J, Kim Y S, et al. Electromagnetic saturation of angstrom-sized quantum barriers at terahertz frequencies[J]. Physical Review Letters, 2015, 115(12): 125501.

[16] Hafez H A, Kovalev S, Deinert J C, et al. Extremely efficient terahertz high-harmonic generation in graphene by hot Dirac fermions[J]. Nature, 2018, 561(7724): 507-511.

[17] Reimann J, Schlauderer S, Schmid C P, et al. Subcycle observation of lightwave-driven Dirac currents in a topological surface band[J]. Nature, 2018, 562(7727): 396-400.

[18] Kang T. Kim R H J Y, Choi G, et al. Terahertz rectification in ring-shaped quantum barriers[J]. Nature Communications, 2018, 9: 4914.

[19] Vampa G, Hammond T J, Taucer M, et al. Strong-field optoelectronics in solids[J]. Nature Photonics, 2018, 12(8): 465-468.

[20] Bonetti S, Hoffmann MC, Sher M J, et al. THz-driven ultrafast spin-lattice scattering in amorphous metallic ferromagnets[J]. Physical Review Letters, 2016, 117(8): 087205.

[21] Kovalev S, Wang Z, Deinert J C, et al. Selective THz control of magnetic order: new opportunities from superradiant undulator sources[J]. Journal of Physics D: Applied Physics, 2018, 51(11): 114007.

[22] Stojanovic N, Drescher M. Accelerator- and laser-based sources of high-field terahertz pulses[J]. Journal of Physics B: Atomic, Molecular and Optical Physics, 2013, 46(19): 192001.

[23] Kim K Y, Taylor A J, Glownia J H, et al. Coherent control of terahertz supercontinuum generation in ultrafast laser-gas interactions[J]. Nature Photonics, 2008, 2(10): 605-609.

[24] Shangguan M J, Xia H Y, Wang C, et al. All-fiber upconversion high spectral resolution wind lidar using a Fabry-Perot interferometer[J]. Optics Express, 2016, 24(17): 19322-19336.

[25] Liao G Q, Li Y T, Zhang Y H, et al. Demonstration of coherent terahertz transition radiation from relativistic laser-solid interactions[J]. Physical Review Letters, 2016, 116(20): 205003.

[26] Liao GQ, LiuH, Li YT, et al. THz pulses over 50 millijoules generated from relativistic picosecond laser-plasma interactions[EB/OL]. ( 2018-05-11)[2018-11-25]. org/abs/1805. 04369. https://arxiv.

[27] Vicario C, Ovchinnikov A V, Ashitkov S I, et al. Generation of 0.9-mJ THz pulses in DSTMS pumped by a Cr∶Mg2SiO4 laser[J]. Optics Letters, 2014, 39(23): 6632-6635.

[28] Huang S W, Granados E, Huang W R, et al. High conversion efficiency, high energy terahertz pulses by optical rectification in cryogenically cooled lithium niobate[J]. Optics Letters, 2013, 38(5): 796-798.

[29] Fülöp J A, Ollmann Z, Lombosi C, et al. Efficient generation of THz pulses with 0.4 mJ energy[J]. Optics Express, 2014, 22(17): 20155-20163.

[30] Fülöp J A, Polónyi G, Monoszlai B, et al. Highly efficient scalable monolithic semiconductor terahertz pulse source[J]. Optica, 2016, 3(10): 1075-1078.

[31] Zhang Z L, Chen Y P, Cui S, et al. Manipulation of polarizations for broadband terahertz waves emitted from laser plasma filaments[J]. Nature Photonics, 2018, 12(9): 554-559.

[32] Wang W M, Gibbon P, Sheng Z M, et al. Tunable circularly polarized terahertz radiation from magnetized gas plasma[J]. Physical Review Letters, 2015, 114(25): 253901.

[33] Yardimci N T, Yang S H, Berry C W, et al. High-power terahertz generation using large-area plasmonic photoconductive emitters[J]. IEEE Transactions on Terahertz Science and Technology, 2015, 5(2): 223-229.

[34] Gopal A, Singh P, Herzer S, et al. Characterization of 700 μJ T rays generated during high-power laser solid interaction[J]. Optics Letters, 2013, 38(22): 4705-4707.

[35] Chai X, Ropagnol X. Raeis-Zadeh S M, et al. Subcycle terahertz nonlinear optics[J]. Physical Review Letters, 2018, 121(14): 143901.

[36] Vicario C, Shalaby M, Hauri C P. Subcycle extreme nonlinearities in GaP induced by an ultrastrong terahertz field[J]. Physical Review Letters, 2017, 118(8): 083901.

[37] Blanchard F, Razzari L, Bandulet H C, et al. Generation of 1.5 μJ single-cycle terahertz pulses by optical rectification from a large aperture ZnTe crystal[J]. Optics Express, 2007, 15(20): 13212-13220.

[38] Shalaby M, Hauri C P. Demonstration of a low-frequency three-dimensional terahertz bullet with extreme brightness[J]. Nature Communications, 2015, 6: 5976.

[39] Shalaby M, Hauri C P. Air nonlinear dynamics initiated by ultra-intense lambda-cubic terahertz pulses[J]. Applied Physics Letters, 2015, 106(18): 181108.

[40] Shalaby M, Vicario C, Hauri C P. Low frequency terahertz-induced demagnetization in ferromagnetic nickel[J]. Applied Physics Letters, 2016, 108(18): 182903.

[41] Giorgianni F, Vicario C, Shalaby M, et al. High-efficiency and low distortion photoacoustic effect in 3D graphene sponge[J]. Advanced Functional Materials, 2018, 28(2): 1702652.

[42] Monoszlai B, Vicario C, Jazbinsek M, et al. High-energy terahertz pulses from organic crystals: DAST and DSTMS pumped at Ti∶sapphire wavelength[J]. Optics Letters, 2013, 38(23): 5106-5109.

[43] Hebling J, Almasi G, Kozma I, et al. Velocity matching by pulse front tilting for large area THz-pulse generation[J]. Optics Express, 2002, 10(21): 1161-1166.

[44] Ravi K, Huang W R, Carbajo S, et al. Limitations to THz generation by optical rectification using tilted pulse fronts[J]. Optics Express, 2014, 22(17): 20239-20251.

[45] Yang K H, Richards P L, Shen Y R. Generation of far-infrared radiation by picosecond light pulses in LiNbO3[J]. Applied Physics Letters, 1971, 19(9): 320-323.

[46] Yeh K L, Hoffmann M C, Hebling J, et al. Generation of 10 μJ ultrashort terahertz pulses by optical rectification[J]. Applied Physics Letters, 2007, 90(17): 171121.

[47] Hoffmann M C, Yeh K L, Hebling J, et al. Efficient terahertz generation by optical rectification at 1035 nm[J]. Optics Express, 2007, 15(18): 11706-11713.

[48] Pálfalvi L, Fülöp J A, Almási G, et al. Novel setups for extremely high power single-cycle terahertz pulse generation by optical rectification[J]. Applied Physics Letters, 2008, 92(17): 171107.

[49] Bakunov M I, Bodrov S B, Tsarev M V. Terahertz emission from a laser pulse with tilted front: phase-matching versus Cherenkov effect[J]. Journal of Applied Physics, 2008, 104(7): 073105.

[50] Hebling J, Yeh K L, Hoffmann M C, et al. Generation of high-power terahertz pulses by tilted-pulse-front excitation and their application possibilities[J]. Journal of the Optical Society of America B, 2008, 25(7): B6-B19.

[51] Stepanov A G, Bonacina L, Chekalin S V, et al. Generation of 30 μJ single-cycle terahertz pulses at 100 Hz repetition rate by optical rectification[J]. Optics Letters, 2008, 33(21): 2497-2499.

[52] Werley C A, Nelson K A. Generation of multicycle terahertz phonon-polariton waves in a planar waveguide by tilted optical pulse fronts[J]. Applied Physics Letters, 2009, 95(10): 103304.

[53] Bodrov S B, Stepanov A N, Bakunov M I, et al. Highly efficient optical-to-terahertz conversion in a sandwich structure with LiNbO3 core[J]. Optics Express, 2009, 17(3): 1871-1878.

[54] Gorunski N, Dimitrov N, Dreischuh A, et al. Pulse-front tilt created in misaligned dispersionless optical systems and correct interferometric autocorrelation[J]. Optics Communications, 2010, 283(24): 5192-5198.

[55] Hebling J, Hoffmann M C, Hwang H Y, et al. Observation of nonequilibrium carrier distribution in Ge, Si, and GaAs by terahertz pump-terahertz probe measurements[J]. Physical Review B, 2010, 81(3): 035201.

[56] Fülöp J A, Pálfalvi L, Almási G, et al. Design of high-energy terahertz sources based on optical rectification[J]. Optics Express, 2010, 18(12): 12311-12327.

[57] Hirori H, Doi A, Blanchard F, et al. Single-cycle terahertz pulses with amplitudes exceeding 1 MV/cm generated by optical rectification in LiNbO3[J]. Applied Physics Letters, 2011, 98(9): 091106.

[58] Fülöp J A, Pálfalvi L, Hoffmann M C, et al. Towards generation of mJ-level ultrashort THz pulses by optical rectification[J]. Optics Express, 2011, 19(16): 15090-15097.

[59] Fülöp J A, Pálfalvi L, Klingebiel S, et al. Generation of sub-mJ terahertz pulses by optical rectification[J]. Optics Letters, 2012, 37(4): 557-559.

[60] Ropagnol X, Morandotti R, Ozaki T, et al. THz pulse shaping and improved optical-to-THz conversion efficiency using a binary phase mask[J]. Optics Letters, 2011, 36(14): 2662-2664.

[61] Ollmann Z, Hebling J, Almási G. Design of a contact grating setup for mJ-energy THz pulse generation by optical rectification[J]. Applied Physics B, 2012, 108(4): 821-826.

[62] Bakunov M I, Tsarev M V, Mashkovich E A. Terahertz difference-frequency generation by tilted amplitude front excitation[J]. Optics Express, 2012, 20(27): 28573-28585.

[63] Avestisyan Y, Zhang C H, Kawayama I, et al. Terahertz generation by optical rectification in lithium niobate crystal using a shadow mask[J]. Optics Express, 2012, 20(23): 25752-25757.

[64] Bodrov S B, Murzanev A A, Sergeev Y A, et al. Terahertz generation by tilted-front laser pulses in weakly and strongly nonlinear regimes[J]. Applied Physics Letters, 2013, 103(25): 251103.

[65] Kunitski M, Richter M, Thomson M D, et al. Optimization of single-cycle terahertz generation in LiNbO3 for sub-50 femtosecond pump pulses[J]. Optics Express, 2013, 21(6): 6826-6836.

[66] Fan S Z, Takeuchi H, Ouchi T, et al. Broadband terahertz wave generation from a MgO∶LiNbO3 ridge waveguide pumped by a 1.5 μm femtosecond fiber laser[J]. Optics Letters, 2013, 38(10): 1654-1656.

[67] Vicario C, Monoszlai B, Lombosi C, et al. Pump pulse width and temperature effects in lithium niobate for efficient THz generation[J]. Optics Letters, 2013, 38(24): 5373-5376.

[68] Sivarajah P, Werley C A. Ofori-Okai B K, et al. Chemically assisted femtosecond laser machining for applications in LiNbO3 and LiTaO3[J]. Applied Physics A, 2013, 112(3): 615-622.

[69] Stepanov A G, Hebling J, Kuhl J. Efficient generation of subpicosecond terahertz radiation by phase-matched optical rectification using ultrashort laser pulses with tilted pulse fronts[J]. Applied Physics Letters, 2003, 83(15): 3000-3002.

[70] Hebling J, Stepanov A G, Almási G, et al. Tunable THz pulse generation by optical rectification of ultrashort laser pulses with tilted pulse fronts[J]. Applied Physics B: Lasers and Optics, 2004, 78(5): 593-599.

[71] Stepanov A G, Kuhl J, Kozma I Z, et al. Scaling up the energy of THz pulses created by optical rectification[J]. Optics Express, 2005, 13(15): 5762-5768.

[72] Zhu LG, Zhong SC, LiJ, et al. Generation of 0.19-mJ THz pulses in LiNbO3 driven by 800-nm femtosecond laser[C]∥2016 41st International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), September 25-30, 2016, Copenhagen, Denmark. New York: IEEE, 2016: 7758391.

[73] Wu X J, Ma J L, Zhang B L, et al. Highly efficient generation of 0.2 mJ terahertz pulses in lithium niobate at room temperature with sub-50 fs chirped Ti∶sapphire laser pulses[J]. Optics Express, 2018, 26(6): 7107-7716.

[74] Wu X J, Chai S S, Ma J L, et al. Optimization of highly efficient terahertz generation in lithium niobate driven by Ti∶sapphire laser pulses with 30 fs pulse duration[J]. Chinese Optics Letters, 2018, 16(4): 041901.

[75] Lombosi C, Polónyi G, Mechler M, et al. Nonlinear distortion of intense THz beams[J]. New Journal of Physics, 2015, 17(8): 083041.

[76] Tsubouchi M, Nagashima K, Yoshida F, et al. Contact grating device with Fabry-Perot resonator for effective terahertz light generation[J]. Optics Letters, 2014, 39(18): 5439-5442.

[77] Vidal S, Degert J, Tondusson M, et al. Optimized terahertz generation via optical rectification in ZnTe crystals[J]. Journal of the Optical Society of America B, 2014, 31(1): 149-153.

[78] Baek I H, Kang B J, Jeong Y U, et al. Diffraction-limited high-power single-cycle terahertz pulse generation in prism-cut LiNbO3for precise terahertz applications[J]. Journal of the Optical Society of Korea, 2014, 18(1): 60-64.

[79] Ronny Huang W, Huang S W, Granados E, et al. Highly efficient terahertz pulse generation by optical rectification in stoichiometric and cryo-cooled congruent lithium niobate[J]. Journal of Modern Optics, 2015, 62(18): 1486-1493.

[80] Zhang S T, Asoubar D, Kammel R, et al. Analysis of pulse front tilt in simultaneous spatial and temporal focusing[J]. Journal of the Optical Society of America A, 2014, 31(11): 2437-2446.

[81] Bakunov M I, Bodrov S B. Terahertz generation with tilted-front laser pulses in a contact-grating scheme[J]. Journal of the Optical Society of America B, 2014, 31(11): 2549-2557.

[82] Ollmann Z, Fülöp J A, Hebling J, et al. Design of a high-energy terahertz pulse source based on ZnTe contact grating[J]. Optics Communications, 2014, 315: 159-163.

[83] Blanchard F, Ropagnol X, Hafez H, et al. Effect of extreme pump pulse reshaping on intense terahertz emission in lithium niobate at multimilliJoule pump energies[J]. Optics Letters, 2014, 39(15): 4333-4336.

[84] Yoshida F, Nagashima K, Tsubouchi M, et al. High-efficiency contact grating fabricated on the basis of a Fabry-Perot type resonator for terahertz wave generation[J]. Japanese Journal of Applied Physics, 2016, 55(1): 012201.

[85] RaviK, CarbajoS, Huang WR, et al. Self-limiting property of terahertz generation by optical rectification using tilted-pulse-fronts[C]∥The European Conference on Lasers and Electro-Optics 2015, June 21-25, 2015, Munich, Germany. Washington D. C.: OSA, 2015: 100- 104.

[86] PálfalviL, OllmannZ, TokodiL, et al. Hybrid tilted-pulse-front excitation scheme for efficient generation of high-energy terahertz pulses[C]∥2016 41st International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), September 25-30, 2016, Copenhagen, Denmark. New York: IEEE, 2016: 7759010.

[87] Ofori-Okai B K, Sivarajah P, Ronny Huang W, et al. . THz generation using a reflective stair-step echelon[J]. Optics Express, 2016, 24(5): 5057-5068.

[88] Pálfalvi L, Tóth G, Tokodi L, et al. Numerical investigation of a scalable setup for efficient terahertz generation using a segmented tilted-pulse-front excitation[J]. Optics Express, 2017, 25(24): 29560-29573.

[89] Matsunaga R, Tsuji N, Fujita H, et al. Light-induced collective pseudospin precession resonating with Higgs mode in a superconductor[J]. Science, 2014, 345(6201): 1145-1149.

[90] Cocker T L, Jelic V, Gupta M, et al. An ultrafast terahertz scanning tunnelling microscope[J]. Nature Photonics, 2013, 7(8): 620-625.

[91] Sie E J, Nyby C M, Pemmaraju C D, et al. An ultrafast symmetry switch in a Weyl semimetal[J]. Nature, 2019, 565(7737): 61-66.

[92] Wu X J, Carbajo S, Ravi K, et al. Terahertz generation in lithium niobate driven by Ti∶sapphire laser pulses and its limitations[J]. Optics Letters, 2014, 39(18): 5403-5436.

[93] Stepanov A G, Henin S, Petit Y, et al. Mobile source of high-energy single-cycle terahertz pulses[J]. Applied Physics B, 2010, 101(1/2): 11-14.

[94] Wu XJ, RaviK, Ronny Huang WQ, et al. Half-percent terahertz generation efficiency from cryogenically cooled lithium niobate pumped by Ti∶sapphire laser pulses[EB/OL]. ( 2016-01-26)[2018-11-25]. org/abs/1601. 06921. https://arxiv.

[95] Pálfalvi L, Hebling J, Kuhl J, et al. Temperature dependence of the absorption and refraction of Mg-doped congruent and stoichiometric LiNbO3 in the THz range[J]. Journal of Applied Physics, 2005, 97(12): 123505.

[96] Wu X J, Zhou C, Huang W R, et al. Temperature dependent refractive index and absorption coefficient of congruent lithium niobate crystals in the terahertz range[J]. Optics Express, 2015, 23(23): 29729-29737.

[97] Sun Y M, Mao Z L, Hou B H, et al. Giant birefringence of lithium niobate crystals in the terahertz region[J]. Chinese Physics Letters, 2007, 24(2): 414-417.

[98] Bakunov M I, Bodrov S B, Mashkovich E A. Terahertz generation with tilted-front laser pulses: dynamic theory for low-absorbing crystals[J]. Journal of the Optical Society of America B, 2011, 28(7): 1724-1734.

[99] Zhang D, Fallahi A, Hemmer M, et al. Segmented terahertz electron accelerator and manipulator (STEAM)[J]. Nature Photonics, 2018, 12(6): 336-342.

[100] Ronny Huang W, Fallahi A, Wu X J, et al. Terahertz-driven, all-optical electron gun[J]. Optica, 2016, 3(11): 1209-1212.

[101] Seifert T, Jaiswal S, Sajadi M, et al. Ultrabroadband single-cycle terahertz pulses with peak fields of 300 kV/cm from a metallic spintronic emitter[J]. Applied Physics Letters, 2017, 110(25): 252402.

[102] Kampfrath T, Battiato M, Maldonado P, et al. Terahertz spin current pulses controlled by magnetic heterostructures[J]. Nature Nanotechnology, 2013, 8(4): 256-260.

[103] Seifert T, Jaiswal S, Martens U, et al. Efficient metallic spintronic emitters of ultrabroadband terahertz radiation[J]. Nature Photonics, 2016, 10(7): 483-488.

[104] Yang D W, Liang J H, Zhou C, et al. Powerful and tunable THz emitters based on the Fe/Pt magnetic heterostructure[J]. Advanced Optical Materials, 2016, 4(12): 1944-1949.

[105] Huisman T J, Mikhaylovskiy R V, Costa J D, et al. Femtosecond control of electric currents in metallic ferromagnetic heterostructures[J]. Nature Nanotechnology, 2016, 11(5): 455-458.

[106] Wu Y, Elyasi M, Qiu X P, et al. High-performance THz emitters based on ferromagnetic/nonmagnetic heterostructures[J]. Advanced Materials, 2017, 29(4): 1603031.

[107] Feng Z, Yu R, Zhou Y, et al. Highly efficient spintronic terahertz emitter enabled by metal-dielectric photonic crystal[J]. Advanced Optical Materials, 2018, 6(23): 1800965.

[108] Seifert T S, Jaiswal S, Barker J, et al. Femtosecond formation dynamics of the spin Seebeck effect revealed by terahertz spectroscopy[J]. Nature Communications, 2018, 9: 2899.

[109] Zhou C, Liu Y P, Wang Z, et al. Broadband terahertz generation via the interface inverse rashba-edelstein effect[J]. Physical Review Letters, 2018, 121(8): 086801.

[110] Jungfleisch M B, Zhang Q, Zhang W, et al. Control of terahertz emission by ultrafast spin-charge current conversion at rashba interfaces[J]. Physical Review Letters, 2018, 120(20): 207207.

[111] Jin Q. E Y W, Williams K, et al. Observation of broadband terahertz wave generation from liquid water[J]. Applied Physics Letters, 2017, 111(7): 071103.

[112] E Y W. Jin Q, Tcypkin A, et al. Terahertz wave generation from liquid water films via laser-induced breakdown[J]. Applied Physics Letters, 2018, 113(18): 181103.