[1] Salières P, Le Déroff L, Auguste T et al. Frequency-domain interferometry in the XUV with high-order harmonics[J]. Physical Review Letters, 83, 5483-5486(1999).
[2] Cavalieri A L, Müller N, Uphues T et al. Attosecond spectroscopy in condensed matter[J]. Nature, 449, 1029-1032(2007).
[3] Li W, Zhou X B, Lock R et al. Time-resolved dynamics in N2O4 probed using high harmonic generation[J]. Science, 322, 1207-1211(2008).
[4] Wörner H J, Bertrand J B, Kartashov D V et al. Following a chemical reaction using high-harmonic interferometry[J]. Nature, 466, 604-607(2010).
[5] He L X, Sun S Q, Lan P F et al. Filming movies of attosecond charge migration in single molecules with high harmonic spectroscopy[J]. Nature Communications, 13, 1-9(2022).
[6] Peng P, Mi Y H, Lytova M et al. Coherent control of ultrafast extreme ultraviolet transient absorption[J]. Nature Photonics, 16, 45-51(2022).
[7] Dai C, Wang Y, Miao Z M et al. Generation and application of high-order harmonics based on interaction between femtosecond laser and matter[J]. Laser & Optoelectronics Progress, 58, 0300001(2021).
[8] Burnett N H, Baldis H A, Richardson M C et al. Harmonic generation in CO2 laser target interaction[J]. Applied Physics Letters, 31, 172-174(1977).
[9] McPherson A, Gibson G, Jara H et al. Studies of multiphoton production of vacuum-ultraviolet radiation in the rare gases[J]. Journal of the Optical Society of America B, 4, 595-601(1987).
[10] Corkum P B. Plasma perspective on strong field multiphoton ionization[J]. Physical Review Letters, 71, 1994-1997(1993).
[11] Peng P, Marceau C, Villeneuve D M. Attosecond imaging of molecules using high harmonic spectroscopy[J]. Nature Reviews Physics, 1, 144-155(2019).
[12] Möller M, Cheng Y, Khan S D et al. Dependence of high-order-harmonic-generation yield on driving-laser ellipticity[J]. Physical Review A, 86, 011401(2012).
[13] Kfir O, Grychtol P, Turgut E et al. Generation of bright phase-matched circularly-polarized extreme ultraviolet high harmonics[J]. Nature Photonics, 9, 99-105(2015).
[14] Gariepy G, Leach J, Kim K T et al. Creating high-harmonic beams with controlled orbital angular momentum[J]. Physical Review Letters, 113, 153901(2014).
[15] Poynting J H. The wave motion of a revolving shaft, and a suggestion as to the angular momentum in a beam of circularly polarised light[J]. Proceedings of the Royal Society of London Series A, Containing Papers of a Mathematical and Physical Character, 82, 560-567(1909).
[16] Beth R A. Mechanical detection and measurement of the angular momentum of light[J]. Physical Review, 50, 115-125(1936).
[17] Allen L, Beijersbergen M W, Spreeuw R J et al. Orbital angular momentum of light and the transformation of Laguerre-Gaussian laser modes[J]. Physical Review A, 45, 8185-8189(1992).
[18] Qian W R, Zhang Y M. Research progress of detecting orbital angular momentum states of photons through metasurfaces[J]. Laser & Optoelectronics Progress, 59, 2300004(2022).
[19] Aiello A, Banzer P, Neugebauer M et al. From transverse angular momentum to photonic wheels[J]. Nature Photonics, 9, 789-795(2015).
[20] Neugebauer M, Banzer P, Bauer T et al. Geometric spin Hall effect of light in tightly focused polarization-tailored light beams[J]. Physical Review A, 89, 013840(2014).
[21] Cao Q, Zhan Q W. Spatiotemporal sculpturing of light and recent development in spatiotemporal optical vortices wavepackets (invited)[J]. Acta Photonica Sinica, 51, 0151102(2022).
[22] Fang Y Q, Lu S Y, Liu Y Q. Controlling photon transverse orbital angular momentum in high harmonic generation[J]. Physical Review Letters, 127, 273901(2021).
[23] Wan C H, Chen J, Chong A et al. Photonic orbital angular momentum with controllable orientation[J]. National Science Review, 9, nwab149(2022).
[24] Bliokh K Y, Rodríguez-Fortuño F J, Nori F et al. Spin-orbit interactions of light[J]. Nature Photonics, 9, 796-808(2015).
[25] Zhao Y Q, Edgar J S, Jeffries G D M et al. Spin-to-orbital angular momentum conversion in a strongly focused optical beam[J]. Physical Review Letters, 99, 073901(2007).
[26] Fang Y Q, Han M, Ge P P et al. Photoelectronic mapping of the spin-orbit interaction of intense light fields[J]. Nature Photonics, 15, 115-120(2021).
[27] Chen J, Yu L H, Wan C H et al. Spin-orbit coupling within tightly focused circularly polarized spatiotemporal vortex wavepacket[J]. ACS Photonics, 9, 793-799(2022).
[28] Yi L Q. High-harmonic generation and spin-orbit interaction of light in a relativistic oscillating window[J]. Physical Review Letters, 126, 134801(2021).
[29] Brasselet E, Izdebskaya Y, Shvedov V et al. Dynamics of optical spin-orbit coupling in uniaxial crystals[J]. Optics Letters, 34, 1021-1023(2009).
[30] Long S, Becker W, McIver J K. Model calculations of polarization-dependent two-color high-harmonic generation[J]. Physical Review A, 52, 2262-2278(1995).
[31] Eichmann H, Egbert A, Nolte S et al. Polarization-dependent high-order two-color mixing[J]. Physical Review A, 51, R3414-R3417(1995).
[32] Fan T T, Grychtol P, Knut R et al. Bright circularly polarized soft X-ray high harmonics for X-ray magnetic circular dichroism[J]. Proceedings of the National Academy of Sciences of the United States of America, 112, 14206-14211(2015).
[33] Qiao Y, Wu D, Chen J G et al. High-order harmonic generation from H2+ irradiated by a co-rotating two-color circularly polarized laser field[J]. Physical Review A, 100, 063428(2019).
[34] Hickstein D D, Dollar F J, Grychtol P et al. Non-collinear generation of angularly isolated circularly polarized high harmonics[J]. Nature Photonics, 9, 743-750(2015).
[35] Dorney K M, Ellis J L, Hernández-García C et al. Helicity-selective enhancement and polarization control of attosecond high harmonic waveforms driven by bichromatic circularly polarized laser fields[J]. Physical Review Letters, 119, 063201(2017).
[36] Shao R Z, Zhai C Y, Zhang Y F et al. Generation of isolated circularly polarized attosecond pulses by three-color laser field mixing[J]. Optics Express, 28, 15874-15884(2020).
[37] Medišauskas L, Wragg J, van der Hart H et al. Generating isolated elliptically polarized attosecond pulses using bichromatic counterrotating circularly polarized laser fields[J]. Physical Review Letters, 115, 153001(2015).
[38] Fang Y Q, Liu Y Q. Optimal control over high-order-harmonic ellipticity in two-color cross-linearly-polarized laser fields[J]. Physical Review A, 103, 033116(2021).
[39] Wätzel J, MultipolarBerakdar J.. polarization-shaped high-order harmonic generation by intense vector beams[J]. Physical Review A, 101, 043409(2020).
[40] Zürch M, Kern C, Hansinger P et al. Strong-field physics with singular light beams[J]. Nature Physics, 8, 743-746(2012).
[41] Géneaux R, Camper A, Auguste T et al. Synthesis and characterization of attosecond light vortices in the extreme ultraviolet[J]. Nature Communications, 7, 1-6(2016).
[42] Hernández-García C, Picón A, San Román J et al. Attosecond extreme ultraviolet vortices from high-order harmonic generation[J]. Physical Review Letters, 111, 083602(2013).
[43] Kong F Q, Zhang C M, Bouchard F et al. Controlling the orbital angular momentum of high harmonic vortices[J]. Nature Communications, 8, 1-6(2017).
[44] Rego L, Román J S, Picón A et al. Nonperturbative twist in the generation of extreme-ultraviolet vortex beams[J]. Physical Review Letters, 117, 163202(2016).
[45] Li S S, Shen B F, Zhang X M et al. Conservation of orbital angular momentum for high harmonic generation of fractional vortex beams[J]. Optics Express, 26, 23460-23470(2018).
[46] Rego L, Dorney K M, Brooks N J et al. Generation of extreme-ultraviolet beams with time-varying orbital angular momentum[J]. Science, 364, eaaw9486(2019).
[47] Babiker M, Bennett C R, Andrews D L et al. Orbital angular momentum exchange in the interaction of twisted light with molecules[J]. Physical Review Letters, 89, 143601(2002).
[48] Hernández-García C, Pérez-Hernández J A, Ramos J et al. High-order harmonic propagation in gases within the discrete dipole approximation[J]. Physical Review A, 82, 033432(2010).
[49] De Ninno G, Wätzel J, Ribič P R et al. Photoelectric effect with a twist[J]. Nature Photonics, 14, 554-558(2020).
[50] Ye L Z, Rouxel J R, Asban S et al. Probing molecular chirality by orbital-angular-momentum-carrying X-ray pulses[J]. Journal of Chemical Theory and Computation, 15, 4180-4186(2019).
[51] Jhajj N, Larkin I, Rosenthal E W et al. Spatiotemporal optical vortices[J]. Physical Review X, 6, 031037(2016).
[52] Hancock S W, Zahedpour S, Goffin A et al. Free-space propagation of spatiotemporal optical vortices[J]. Optica, 6, 1547-1553(2019).
[53] Chong A, Wan C H, Chen J et al. Generation of spatiotemporal optical vortices with controllable transverse orbital angular momentum[J]. Nature Photonics, 14, 350-354(2020).
[54] Hancock S W, Zahedpour S, Milchberg H M. Second-harmonic generation of spatiotemporal optical vortices and conservation of orbital angular momentum[J]. Optica, 8, 594-597(2021).
[55] Gui G, Brooks N J, Kapteyn H C et al. Second-harmonic generation and the conservation of spatiotemporal orbital angular momentum of light[J]. Nature Photonics, 15, 608-613(2021).
[56] Chen Z Y, Hu R H, Zhang S et al. Relativistic high-order harmonic generation of spatiotemporal optical vortices[J]. Physical Review A, 106, 013516(2022).
[57] Zhang L G, Ji L L, Shen B F. Intense harmonic generation driven by a relativistic spatiotemporal vortex beam[J]. High Power Laser Science and Engineering, 10, e46(2022).
[58] Ballantine K E, Donegan J F, Eastham P R. There are many ways to spin a photon: half-quantization of a total optical angular momentum[J]. Science Advances, 2, e1501748(2016).
[59] Pisanty E, Machado G J, Vicuña-Hernández V et al. Knotting fractional-order knots with the polarization state of light[J]. Nature Photonics, 13, 569-574(2019).
[60] Pisanty E, Rego L, San Román J et al. Conservation of torus-knot angular momentum in high-order harmonic generation[J]. Physical Review Letters, 122, 203201(2019).
[61] Dorney K M, Rego L, Brooks N J et al. Controlling the polarization and vortex charge of attosecond high-harmonic beams via simultaneous spin–orbit momentum conservation[J]. Nature Photonics, 13, 123-130(2019).
[62] Minneker B, Böning B, Weber A et al. Torus-knot angular momentum in twisted attosecond pulses from high-order harmonic generation[J]. Physical Review A, 104, 053116(2021).
[63] Hernández-García C, Turpin A, Román J S et al. Extreme ultraviolet vector beams driven by infrared lasers[J]. Optica, 4, 520-526(2017).
[64] Kong F, Zhang C, Larocque H et al. Vectorizing the spatial structure of high-harmonic radiation from gas[J]. Nature Communications, 10, 1-6(2019).
[65] Kong F, Zhang C, Larocque H et al. Spin-constrained orbital-angular-momentum control in high-harmonic generation[J]. Physical Review Research, 1, 032008(2019).
[66] Xie D, Yin Y, Zhou H Y. Theoretical investigation of high-brightness and circularly polarized high order harmonics excited by intense laser and plasma waveguide[J]. Acta Optica Sinica, 42, 2114001(2022).
[67] Ye L Z, Yang L Q, Zheng X et al. Enhancing circular dichroism signals with vector beams[J]. Physical Review Letters, 126, 123001(2021).
