We present a theoretical study of the one-dimensional modulational instability of a broad optical beam propagating in a biased photorefractive crystal with both linear and quadratic electro-optic effects(Kerr effect)u...We present a theoretical study of the one-dimensional modulational instability of a broad optical beam propagating in a biased photorefractive crystal with both linear and quadratic electro-optic effects(Kerr effect)under steadystate conditions.One-dimensional modulational instability growth rates are obtained by treating the space-charge field equation globally and locally.Both theoretical reasoning and numerical simulation show that both the global and local modulational instability gains are governed simultaneously by the strength and the polarity of external bias field and by the ratio of the intensity of the broad beam to that of the dark irradiance.Under a strong bias field,the results obtained using these two methods are in good agreement in the low spatial frequency regime.Moreover,the instability growth rate increases with the bias field,and the maximum instability growth occurs when ratio of light intensity to dark irradiance is 0.88.展开更多
We investigate theoretically the temperature effects on the evolution and stability of a separate screening brightdark soliton pair formed in a serial non-photovoltaic photorefractive crystal circuit. Our numerical re...We investigate theoretically the temperature effects on the evolution and stability of a separate screening brightdark soliton pair formed in a serial non-photovoltaic photorefractive crystal circuit. Our numerical results show that, for a stable bright-dark soliton pair originally formed in a crystal circuit at given temperatures, when one crystal temperature changes, the soliton supported by the other crystal will evolve into another stable soliton if the temperature change is quite small, whereas it will become unstable and experience larger cycles of compression or break up into beam filaments if the temperature difference is big enough. The dark soliton is more sensitive to the temperature change than the bright one.展开更多
This paper predicts that grey spatial solitons can exist in two-photon photorefractive materials. In steady state and undcr appropriate external bias conditions, it obtains the grey spatial soliton solutions of the op...This paper predicts that grey spatial solitons can exist in two-photon photorefractive materials. In steady state and undcr appropriate external bias conditions, it obtains the grey spatial soliton solutions of the optical wave evolution equation. The intensity profile, phase distribution, and transverse velocity of these grey solitons are discussed.展开更多
This paper investigates the photorefractive properties of iron doped lithium niobate with different [Li]/[Nb] ratios The experimental results show two photorefractive centres for iron doped near-stoichiometric lithium...This paper investigates the photorefractive properties of iron doped lithium niobate with different [Li]/[Nb] ratios The experimental results show two photorefractive centres for iron doped near-stoichiometric lithium niobate crystal Besides Fe^2+ and Fe^3+ ions, small polarons and bipolarons are considered as another photoactive centre.展开更多
A new PVK-based photorefractive polymer composite sensitized by C60 and doped with a higher content of EO chromophore was prepared. The high optical quality thin-film was formed between two ITOcovered glass electrode...A new PVK-based photorefractive polymer composite sensitized by C60 and doped with a higher content of EO chromophore was prepared. The high optical quality thin-film was formed between two ITOcovered glass electrodes. Two-beam-coupling (2BC) experiment was performed by using a He-Ne laser (at wavelength 632.8nm), and an obvious photorefractive performance was observed. The dependence of two-beamcoupling gain coefficient on the applied poling dc electric field was measured.展开更多
Holographic dark (bright) screening solitons are predicted in one dimension for a series circuit consisting of two photorefractive crystals connected electronically by electrode leads in a chain with a voltage sourc...Holographic dark (bright) screening solitons are predicted in one dimension for a series circuit consisting of two photorefractive crystals connected electronically by electrode leads in a chain with a voltage source. Each crystal can support a holographic screening soliton. The two solitons are known collectively as a separate holographic screening soliton pair with three types: bright-bright, bright-dark and dark-dark. The numerical results show that the two solitons in a soliton pair can affect each other through a light-induced current and their coupling can affect their spatial profiles under the limit in which the optical wave has a spatial extent much less than the width of the crystal.展开更多
The incoherent interaction between solitons with different transverse dimensions in a noncentrosymmetric photorefractive crystal is studied both in theory and in experiment. An anomalous incoherent interaction between...The incoherent interaction between solitons with different transverse dimensions in a noncentrosymmetric photorefractive crystal is studied both in theory and in experiment. An anomalous incoherent interaction between one- and two-dimensional solitons, whose attractive and repulsive effects depend on the soliton separation, is numerically demonstrated by employing an anisotropic model. By launching a one-dimensional green beam and a two-dimensional red beam into a biased SBN:60 crystal, the hybrid-dimensional soliton interaction is performed. The experimental results are in good agreement with the numerical ones.展开更多
We have analyzed the photorefractive(PR) effect of a polymer composite was reported which combines a novel bi-functional poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl(PVNPAK) and 2,4,7-trinitro-9-fluorenone(TNF...We have analyzed the photorefractive(PR) effect of a polymer composite was reported which combines a novel bi-functional poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl(PVNPAK) and 2,4,7-trinitro-9-fluorenone(TNF). PVNPAK was synthesized by a post-azo-coupling reaction, with an azo derivative as the electrooptic chromophore and carbazolyl as photoconductive moiety. The asymmetric two-beam coupling gain of 13.9 cm-1 and diffraction efficiency of 1.2% for poled polymer film fabricated using a corona poling are obtained at the wavelength of 647.1 nm, confirming photorefractivity. We interpreted this result as the orientational enhancement, in which the spatial charge field may enhance the modulated orientation of the azobenzen chromophore. It is unexpected that the photorefractive gain of 9.5 cm-1 for the unpoled polymer film also was observed without external field in two-beam coupling(TBC) experiment. This phenomenon is attributed to a light-induced orientational grating when the azobenzene groups are illuminated by polarized light.展开更多
ZnO(4mol%),In 2O 3(1mol%)and Fe 2O 3(0.05mol%)were doped in LiNbO 3 and Czochralski method was used to grow Zn∶In∶Fe∶LiNbO 3 crystal.The diameter of the crystal we grew is 30mm.The technology parameter we took is t...ZnO(4mol%),In 2O 3(1mol%)and Fe 2O 3(0.05mol%)were doped in LiNbO 3 and Czochralski method was used to grow Zn∶In∶Fe∶LiNbO 3 crystal.The diameter of the crystal we grew is 30mm.The technology parameter we took is that the axial temperature gradient is 40℃/cm,the growth rate is 1mm/h, the rotation rate is 15-25r/min,the temperature of polarization is 1220℃ and the current density of polarization is 5mA/cm 2.The wafer dimension is 10mm×10mm×3mm and was covered in Li 2CO 3 powder to reduce.The reduction temperature is 500℃ and reduction time is 30 hours. OH - stretch vibration transmission spectra were measured by Fourier infrared spectrophotometer. There are two absorption peaks in OH - spectra of Zn∶In∶Fe∶LiNbO 3,in which one is at 3534cm -1 (2.83μm) and the other is at 3505cm -1 (2.85μm).The peak at 2.85μm is far lower than that at 2.83μm. Because of the threshold effect of Zn 2+ and In 3+ ,the peak at 2.83μm is generated and the peak at 2.85μm is related with Fe 3+ .In LiNbO 3 only doped with Fe,Li + site is taken place by Fe 3+ .When doping Zn 2+ and In 3+ in high concentration,these two ions take place Nb that is at Li site and Fe 3+ substitutes for Nb 5+ at the same time.The interaction between Fe 3+ and OH - make the OH - peak shift to 2.85μm.展开更多
In this paper, the temporary UV-light-induced absorption in LiNbO3:Fe, Co crystal is investigated for different UV intensities. It is found that the sensitizing process in LiNbO3 :Fe, Co can be considered as a combi...In this paper, the temporary UV-light-induced absorption in LiNbO3:Fe, Co crystal is investigated for different UV intensities. It is found that the sensitizing process in LiNbO3 :Fe, Co can be considered as a combination of two sub-processes with different time constants. Based on the lattice structure and the photochromic mechanism of the material, the two sub-processes are suggested to arise from electron transfer from O^2- to Fe^3+ through two paths with different distances. The two-colour recording experiment in LiNbO3:Fe, Co is also preformed by using UV and green light as gating and writing beams respectively. High sensitivity is obtained in the recording, which is considered as the consequence of direct charge transfer from O^2- to Fe^3+.展开更多
We report an organic/inorganic hybridized nanocomposite consisting of a bi-functional poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl serves as a polymeric charge-transporting and second-order nonliner optical matrix, ...We report an organic/inorganic hybridized nanocomposite consisting of a bi-functional poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl serves as a polymeric charge-transporting and second-order nonliner optical matrix, and CdS nanoparticles as photosensitizers to manifest photorefractive (PR) effect. The unpoled PVNPAK film exhibits a second harmonic generation (SHG) coefficient of 4.7 pm/V due to the possibility of self-alignment of the azo chromophore. Significant enhancement of photoconductivity is noticed with the increase of CdS nanoparticles concentration. The photorefractive property of the polymer nanocomposites were determined by two-beam coupling (TBC) experiment. The TBC gain and diffraction efficiency of 11.89 cm-1 and 3.2% were obtained for PVNPAK/CdS at zero electrical field.展开更多
We investigate the properties of waveguides induced by one-dimensional grey screening solitons in biased photorefractive crystals. The results show that waveguides induced by grey screening solitons are always of sing...We investigate the properties of waveguides induced by one-dimensional grey screening solitons in biased photorefractive crystals. The results show that waveguides induced by grey screening solitons are always of single mode for all intensity ratios, i,e. the ratios between the peak intensity of the soliton and the dark irradiance. Our analysis indicates that the energy confined near the centre of the grey soliton and the propagation constant of the guided mode of the waveguide induced by the grey screening soliton increase monotonically with intensity ratio increasing. On the other hand, when the soliton greyness increases, the energy confined near the centre of the grey soliton and the propagation constant of the guided mode of the waveguide induced by the grey screening soliton decrease monotonically. Relevant examples are provided where photorefractive crystal is of the strontium barium niobate type.展开更多
This paper shows that waveguides induced by grey screening-photovoltaic solitons are always single mode for all intensity ratios, which are the ratio between the peak intensity of the soliton and the dark irradiance. ...This paper shows that waveguides induced by grey screening-photovoltaic solitons are always single mode for all intensity ratios, which are the ratio between the peak intensity of the soliton and the dark irradiance. It finds that the confined energy near the centre of the grey soliton and the propagation constant of the guided mode increase monotonically with increasing intensity ratio. On the other hand, when the soliton greyness increases, the confined energy near the centre of the grey soliton and the propagation constant of the guided mode reduce monotonically. When the bulk photovoltaic effect is neglected for short circuits, these waveguides become waveguides induced by grey screening solitons. When the external bias field is absent, these waveguides become waveguides induced by grey photovoltaic solitons.展开更多
Based on the time-dependent band-transport model in a photorefractive medium,dark open-circuit photovoltaic (PV) solitons are investigated both theoretically and experimentally. Compared with those of the time-indep...Based on the time-dependent band-transport model in a photorefractive medium,dark open-circuit photovoltaic (PV) solitons are investigated both theoretically and experimentally. Compared with those of the time-independent models,our theoretical results revealed that quasi-steady-state and steady-state PV solitons can both be obtained.Our results also revealed that when г〈1(г is the normalized intensity at infinity),the full width at half maximum (FWHM) of solitons decreases monotonically to a constant value;when г〉1, however, the FWHM of solitons first decreases to a minimum before it increases to a constant value. Moreover,the FWHM of steady solitons decreases with increasing intensity ratio for г〈1,and increases with increasing intensity ratio for г〉1.We further observed dark PV solitons in experiments,and recorded their evolution.These results indicated that steady solitons can be observed at low optical power,while quasi-steady-state solitons can only be generated at higher optical power. Good agreement is found between theory and experiment.展开更多
A new scheme for recording a dynamic phase grating with an asymmetric profile in C60-doped homeotropically aligned nematic liquid crystal(NLC) was presented.An oblique incidence beam was used to record the thin asym...A new scheme for recording a dynamic phase grating with an asymmetric profile in C60-doped homeotropically aligned nematic liquid crystal(NLC) was presented.An oblique incidence beam was used to record the thin asymmetric dynamic phase holographic grating.The diffraction efficiency we achieved is more than 40%,exceeding the theoretical limit for symmetric profile gratings.Both facts can be explained by assuming that a grating with an asymmetric saw-tooth profile is formed in the NLC.Finally,physical mechanism and mathematical model for characterizing the asymmetric phase holographic grating were presented,based on the photo-refractive-like(PR-like) effect.展开更多
The optical frequency comb based on microresonators(microcombs)is an integrated coherent light source and has the potential to promise a high-precision frequency standard;self-reference and a long-term stable microcom...The optical frequency comb based on microresonators(microcombs)is an integrated coherent light source and has the potential to promise a high-precision frequency standard;self-reference and a long-term stable microcomb are the keys to this realization.Here,we demonstrated a 0.7-octave spectrum Kerr comb via dispersion engineering in a thin-film lithium niobate microresonator,and the single-soliton state can be accessed passively with long-term stability over 3 h.With such a robust broadband coherent comb source using thin-film lithium niobate,a fully stabilized microcomb can be expected for massive practical applications.展开更多
文摘We present a theoretical study of the one-dimensional modulational instability of a broad optical beam propagating in a biased photorefractive crystal with both linear and quadratic electro-optic effects(Kerr effect)under steadystate conditions.One-dimensional modulational instability growth rates are obtained by treating the space-charge field equation globally and locally.Both theoretical reasoning and numerical simulation show that both the global and local modulational instability gains are governed simultaneously by the strength and the polarity of external bias field and by the ratio of the intensity of the broad beam to that of the dark irradiance.Under a strong bias field,the results obtained using these two methods are in good agreement in the low spatial frequency regime.Moreover,the instability growth rate increases with the bias field,and the maximum instability growth occurs when ratio of light intensity to dark irradiance is 0.88.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 10574051 and 10174025) and the Research Foundation for 0utstanding Young Teachers, China University of Geosciences (Grant No CUGQNL0621).
文摘We investigate theoretically the temperature effects on the evolution and stability of a separate screening brightdark soliton pair formed in a serial non-photovoltaic photorefractive crystal circuit. Our numerical results show that, for a stable bright-dark soliton pair originally formed in a crystal circuit at given temperatures, when one crystal temperature changes, the soliton supported by the other crystal will evolve into another stable soliton if the temperature change is quite small, whereas it will become unstable and experience larger cycles of compression or break up into beam filaments if the temperature difference is big enough. The dark soliton is more sensitive to the temperature change than the bright one.
基金Project supported by the National Natural Science Foundation of China (Grant No 60508005), and Scientific Research Foundation of Harbin Institute of Technology of China (Grant No HIT. 2003. 31).
文摘This paper predicts that grey spatial solitons can exist in two-photon photorefractive materials. In steady state and undcr appropriate external bias conditions, it obtains the grey spatial soliton solutions of the optical wave evolution equation. The intensity profile, phase distribution, and transverse velocity of these grey solitons are discussed.
基金Project supported by the research funding via Program for Changjiang Scholars of ChinaInnovative Research Team in University,China+1 种基金the National Natural Science Foundation of China(Grant No60578019)Program for Changjiang Scholars and Innovative Research Team in University
文摘This paper investigates the photorefractive properties of iron doped lithium niobate with different [Li]/[Nb] ratios The experimental results show two photorefractive centres for iron doped near-stoichiometric lithium niobate crystal Besides Fe^2+ and Fe^3+ ions, small polarons and bipolarons are considered as another photoactive centre.
文摘A new PVK-based photorefractive polymer composite sensitized by C60 and doped with a higher content of EO chromophore was prepared. The high optical quality thin-film was formed between two ITOcovered glass electrodes. Two-beam-coupling (2BC) experiment was performed by using a He-Ne laser (at wavelength 632.8nm), and an obvious photorefractive performance was observed. The dependence of two-beamcoupling gain coefficient on the applied poling dc electric field was measured.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10174025 and 10574051)
文摘Holographic dark (bright) screening solitons are predicted in one dimension for a series circuit consisting of two photorefractive crystals connected electronically by electrode leads in a chain with a voltage source. Each crystal can support a holographic screening soliton. The two solitons are known collectively as a separate holographic screening soliton pair with three types: bright-bright, bright-dark and dark-dark. The numerical results show that the two solitons in a soliton pair can affect each other through a light-induced current and their coupling can affect their spatial profiles under the limit in which the optical wave has a spatial extent much less than the width of the crystal.
基金Project supported by the Doctoral Science Foundation of Northwestern Polytechnical University (NPU),China (Grant No. CX200514)the NPU Foundation for Fundamental Research,China
文摘The incoherent interaction between solitons with different transverse dimensions in a noncentrosymmetric photorefractive crystal is studied both in theory and in experiment. An anomalous incoherent interaction between one- and two-dimensional solitons, whose attractive and repulsive effects depend on the soliton separation, is numerically demonstrated by employing an anisotropic model. By launching a one-dimensional green beam and a two-dimensional red beam into a biased SBN:60 crystal, the hybrid-dimensional soliton interaction is performed. The experimental results are in good agreement with the numerical ones.
基金Funded by the National Natural Science Foundation of China(No.51303115)
文摘We have analyzed the photorefractive(PR) effect of a polymer composite was reported which combines a novel bi-functional poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl(PVNPAK) and 2,4,7-trinitro-9-fluorenone(TNF). PVNPAK was synthesized by a post-azo-coupling reaction, with an azo derivative as the electrooptic chromophore and carbazolyl as photoconductive moiety. The asymmetric two-beam coupling gain of 13.9 cm-1 and diffraction efficiency of 1.2% for poled polymer film fabricated using a corona poling are obtained at the wavelength of 647.1 nm, confirming photorefractivity. We interpreted this result as the orientational enhancement, in which the spatial charge field may enhance the modulated orientation of the azobenzen chromophore. It is unexpected that the photorefractive gain of 9.5 cm-1 for the unpoled polymer film also was observed without external field in two-beam coupling(TBC) experiment. This phenomenon is attributed to a light-induced orientational grating when the azobenzene groups are illuminated by polarized light.
文摘ZnO(4mol%),In 2O 3(1mol%)and Fe 2O 3(0.05mol%)were doped in LiNbO 3 and Czochralski method was used to grow Zn∶In∶Fe∶LiNbO 3 crystal.The diameter of the crystal we grew is 30mm.The technology parameter we took is that the axial temperature gradient is 40℃/cm,the growth rate is 1mm/h, the rotation rate is 15-25r/min,the temperature of polarization is 1220℃ and the current density of polarization is 5mA/cm 2.The wafer dimension is 10mm×10mm×3mm and was covered in Li 2CO 3 powder to reduce.The reduction temperature is 500℃ and reduction time is 30 hours. OH - stretch vibration transmission spectra were measured by Fourier infrared spectrophotometer. There are two absorption peaks in OH - spectra of Zn∶In∶Fe∶LiNbO 3,in which one is at 3534cm -1 (2.83μm) and the other is at 3505cm -1 (2.85μm).The peak at 2.85μm is far lower than that at 2.83μm. Because of the threshold effect of Zn 2+ and In 3+ ,the peak at 2.83μm is generated and the peak at 2.85μm is related with Fe 3+ .In LiNbO 3 only doped with Fe,Li + site is taken place by Fe 3+ .When doping Zn 2+ and In 3+ in high concentration,these two ions take place Nb that is at Li site and Fe 3+ substitutes for Nb 5+ at the same time.The interaction between Fe 3+ and OH - make the OH - peak shift to 2.85μm.
基金Project supported by the Natural Science Foundation of Hebei Province,China(Grant Nos.F2007000119 and F2009000108)the Natural Science Foundation of Tianjin,China(Grant No.09JCYBJC02400)the Scientific Research Foundation of Education Bureau of Hebei Province,China(Grant No.2008113)
文摘In this paper, the temporary UV-light-induced absorption in LiNbO3:Fe, Co crystal is investigated for different UV intensities. It is found that the sensitizing process in LiNbO3 :Fe, Co can be considered as a combination of two sub-processes with different time constants. Based on the lattice structure and the photochromic mechanism of the material, the two sub-processes are suggested to arise from electron transfer from O^2- to Fe^3+ through two paths with different distances. The two-colour recording experiment in LiNbO3:Fe, Co is also preformed by using UV and green light as gating and writing beams respectively. High sensitivity is obtained in the recording, which is considered as the consequence of direct charge transfer from O^2- to Fe^3+.
基金Funded by the National Natural Science Foundation of China (No.50802069)the Natural Science Foundation of Wuhan University of Tech-nology (471-38650378)
文摘We report an organic/inorganic hybridized nanocomposite consisting of a bi-functional poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl serves as a polymeric charge-transporting and second-order nonliner optical matrix, and CdS nanoparticles as photosensitizers to manifest photorefractive (PR) effect. The unpoled PVNPAK film exhibits a second harmonic generation (SHG) coefficient of 4.7 pm/V due to the possibility of self-alignment of the azo chromophore. Significant enhancement of photoconductivity is noticed with the increase of CdS nanoparticles concentration. The photorefractive property of the polymer nanocomposites were determined by two-beam coupling (TBC) experiment. The TBC gain and diffraction efficiency of 11.89 cm-1 and 3.2% were obtained for PVNPAK/CdS at zero electrical field.
基金Project supported by the National Natural Science Foundation of China (Grant No 10474136), and the Director Foundation of Xi'an Institute of 0ptics and Precision Mechanics, Chinese Academic of Sciences.
文摘We investigate the properties of waveguides induced by one-dimensional grey screening solitons in biased photorefractive crystals. The results show that waveguides induced by grey screening solitons are always of single mode for all intensity ratios, i,e. the ratios between the peak intensity of the soliton and the dark irradiance. Our analysis indicates that the energy confined near the centre of the grey soliton and the propagation constant of the guided mode of the waveguide induced by the grey screening soliton increase monotonically with intensity ratio increasing. On the other hand, when the soliton greyness increases, the energy confined near the centre of the grey soliton and the propagation constant of the guided mode of the waveguide induced by the grey screening soliton decrease monotonically. Relevant examples are provided where photorefractive crystal is of the strontium barium niobate type.
基金Project supported by the National Natural Science Foundation of China (Grant No 10474136).
文摘This paper shows that waveguides induced by grey screening-photovoltaic solitons are always single mode for all intensity ratios, which are the ratio between the peak intensity of the soliton and the dark irradiance. It finds that the confined energy near the centre of the grey soliton and the propagation constant of the guided mode increase monotonically with increasing intensity ratio. On the other hand, when the soliton greyness increases, the confined energy near the centre of the grey soliton and the propagation constant of the guided mode reduce monotonically. When the bulk photovoltaic effect is neglected for short circuits, these waveguides become waveguides induced by grey screening solitons. When the external bias field is absent, these waveguides become waveguides induced by grey photovoltaic solitons.
基金Project supported by the National Natural Science Foundation of China (Grant No 10674176)
文摘Based on the time-dependent band-transport model in a photorefractive medium,dark open-circuit photovoltaic (PV) solitons are investigated both theoretically and experimentally. Compared with those of the time-independent models,our theoretical results revealed that quasi-steady-state and steady-state PV solitons can both be obtained.Our results also revealed that when г〈1(г is the normalized intensity at infinity),the full width at half maximum (FWHM) of solitons decreases monotonically to a constant value;when г〉1, however, the FWHM of solitons first decreases to a minimum before it increases to a constant value. Moreover,the FWHM of steady solitons decreases with increasing intensity ratio for г〈1,and increases with increasing intensity ratio for г〉1.We further observed dark PV solitons in experiments,and recorded their evolution.These results indicated that steady solitons can be observed at low optical power,while quasi-steady-state solitons can only be generated at higher optical power. Good agreement is found between theory and experiment.
基金Project supported by the Science and Technology Programs of the Educational Committee of Heilongjiang Province,China(Grant No.12541730)the National Natural Science Foundation of China(Grant No.61405057)
文摘A new scheme for recording a dynamic phase grating with an asymmetric profile in C60-doped homeotropically aligned nematic liquid crystal(NLC) was presented.An oblique incidence beam was used to record the thin asymmetric dynamic phase holographic grating.The diffraction efficiency we achieved is more than 40%,exceeding the theoretical limit for symmetric profile gratings.Both facts can be explained by assuming that a grating with an asymmetric saw-tooth profile is formed in the NLC.Finally,physical mechanism and mathematical model for characterizing the asymmetric phase holographic grating were presented,based on the photo-refractive-like(PR-like) effect.
基金This work was supported by the National Key R&D Program of China(Nos.2022YFA1205100,2023YFB2805700,and 2019YFA0705000)the National Natural Science Foundation of China(Nos.62293523 and 12304421)+4 种基金the Leading-edge Technology Program of Jiangsu Natural Science Foundation(No.BK20192001)the Zhangjiang Laboratory(No.ZJSP21A001)the Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030009)the Jiangsu Natural Science Foundation(No.BK20230770)the Jiangsu Funding Program for Excellent Postdoctoral Talent.
文摘The optical frequency comb based on microresonators(microcombs)is an integrated coherent light source and has the potential to promise a high-precision frequency standard;self-reference and a long-term stable microcomb are the keys to this realization.Here,we demonstrated a 0.7-octave spectrum Kerr comb via dispersion engineering in a thin-film lithium niobate microresonator,and the single-soliton state can be accessed passively with long-term stability over 3 h.With such a robust broadband coherent comb source using thin-film lithium niobate,a fully stabilized microcomb can be expected for massive practical applications.