Nonlinear silicon photonics has shown an ability to generate, manipulate, and detect optical signals on an ultracompact chip at a potential low cost. There are still barriers hindering its development due to essential...Nonlinear silicon photonics has shown an ability to generate, manipulate, and detect optical signals on an ultracompact chip at a potential low cost. There are still barriers hindering its development due to essential material limitations. In this review, hybrid structures with some specific materials developed for nonlinear silicon photonics are discussed. The combination of silicon and the nonlinear materials takes advantage of both materials, which shows great potential to improve the performance and expand the applications for nonlinear silicon photonics.展开更多
Hyperentanglement is a promising resource for achieving high capacity quantum communication.Here,we propose a compact scheme for the generation of path-frequency hyperentangled photon pairs via spontaneous parametric ...Hyperentanglement is a promising resource for achieving high capacity quantum communication.Here,we propose a compact scheme for the generation of path-frequency hyperentangled photon pairs via spontaneous parametric down-conversion(SPDC)processes,where six different paths and two different frequencies are covered.A two-dimensional periodicalχ^((2))nonlinear photonic crystal(NPC)is designed to satisfy type-Ⅰquasi-phase-matching conditions in the plane perpendicular to the incident pump beam,and a perfect phase match is achieved along the pump beam's direction to ensure high conversion efficiency,with theoretically estimated photon flux up to 2.068×10^(5) pairs·s^(-1)·mm^(-2).We theoretically calculate the joint-spectral amplitude(JSA)of the generated photon pair and perform Schmidt decomposition on it,where the resulting entropy S of entanglement and effective Schmidt rank K reach 3.2789 and 6.4675,respectively.Our hyperentangled photon source scheme could provide new avenues for high-dimensional quantum communication and high-speed quantum information processing.展开更多
Generation of hyperentangled photon pairs is investigated based on the lithium niobate straight waveguide.We propose to use the nonlinear optical process of spontaneous parametric down-conversion(SPDC)and a well-desig...Generation of hyperentangled photon pairs is investigated based on the lithium niobate straight waveguide.We propose to use the nonlinear optical process of spontaneous parametric down-conversion(SPDC)and a well-designed lithium niobate waveguide structure to generate a hyperentangled(in the polarization dimension and the energy-time dimension)two-photon state.By performing numerical simulations of the waveguide structure and calculating the possible polarization states,joint spectral amplitudes(JSA),and joint temporal amplitudes(JTA)of the generated photon pair,we show that the generated photon pair is indeed hyperentangled in both the polarization dimension and the energy-time dimension.展开更多
We introduce a nanoscale photonic platform based on gallium phosphide. Owing to the favorable material properties, peak power intensity levels of 50 GW∕cm^2 are safely reached in a suspended membrane. Consequently,th...We introduce a nanoscale photonic platform based on gallium phosphide. Owing to the favorable material properties, peak power intensity levels of 50 GW∕cm^2 are safely reached in a suspended membrane. Consequently,the field enhancement is exploited to a far greater extent to achieve efficient and strong light–matter interaction.As an example, parametric interactions are shown to reach a deeply nonlinear regime, revealing cascaded fourwave mixing leading to comb generation and high-order soliton dynamics.展开更多
The field of nonlinear photonics is in full development. This special issue of Photonics Research takes you through the current issues of this fast-growing field of research, drawing on the current state of the art an...The field of nonlinear photonics is in full development. This special issue of Photonics Research takes you through the current issues of this fast-growing field of research, drawing on the current state of the art and seeking, through a selection of articles, to outline some trends for the future.展开更多
Five conical harmonic beams are generated from the interaction of femtosecond mid-infrared(mid-IR) pulses at a nominal input wavelength of 1997 nm with a 2D LiNbO_3 nonlinear photonic crystal with Sierpinski fractal s...Five conical harmonic beams are generated from the interaction of femtosecond mid-infrared(mid-IR) pulses at a nominal input wavelength of 1997 nm with a 2D LiNbO_3 nonlinear photonic crystal with Sierpinski fractal superlattices. The main diffraction orders and the corresponding reciprocal vectors involved in the interaction are ascertained. Second and third harmonics emerging at external angles of 23.82° and 36.75° result from nonlinearerenkov and Bragg diffractions, respectively. Three pathways of fourth-harmonic generation are observed at external angles of 14.21°, 36.5°, and 53.48°, with the first one resulting from nonlinearerenkov diffraction, and the other two harmonics are generated via different cascaded processes.展开更多
Two-dimensional(2D) materials have emerged as attractive mediums for fabricating versatile optoelectronic devices. Recently, few-layer molybdenum disulfide(MoS2), as a shining 2D material, has been discovered to p...Two-dimensional(2D) materials have emerged as attractive mediums for fabricating versatile optoelectronic devices. Recently, few-layer molybdenum disulfide(MoS2), as a shining 2D material, has been discovered to possess both the saturable absorption effect and large nonlinear refractive index. Herein, taking advantage of the unique nonlinear optical properties of MoS2, we fabricated a highly nonlinear saturable absorption photonic device by depositing the few-layer MoS2 onto the microfiber. With the proposed MoS2 photonic device, apart from the conventional soliton patterns, the mode-locked pulses could be shaped into some new soliton patterns, namely,multiple soliton molecules, localized chaotic multipulses, and double-scale soliton clusters. Our findings indicate that the few-layer MoS2-deposited microfiber could operate as a promising highlynonlinear photonic device for the related nonlinear optics applications.展开更多
The nonlinear Talbot effect is a near-field nonlinear diffraction phenomenon in which the self-imaging of periodic objects is formed by the second harmonics of the incident laser beam. We demonstrate the first, to the...The nonlinear Talbot effect is a near-field nonlinear diffraction phenomenon in which the self-imaging of periodic objects is formed by the second harmonics of the incident laser beam. We demonstrate the first, to the best of our knowledge, example of nonlinear Talbot self-healing, i.e., the capability of creating defect-free images from faulty nonlinear optical structures. In particular, we employ the tightly focused femtosecond infrared optical pulses to fabricate LiNbO_(3) nonlinear photonic crystals and show that the defects in the form of the missing points of two-dimensional square and hexagonal periodic structures are restored in the second harmonic images at the first nonlinear Talbot plane. The observed nonlinear Talbot self-healing opens up new possibilities for defect-tolerant optical lithography and printing.展开更多
We investigate in this paper the influence of slow light on the balance between the Kerr and two-photon absorption(TPA) processes in silicon slotted hybrid nonlinear waveguides. Three typical silicon photonic waveguid...We investigate in this paper the influence of slow light on the balance between the Kerr and two-photon absorption(TPA) processes in silicon slotted hybrid nonlinear waveguides. Three typical silicon photonic waveguide geometries are studied to estimate the influence of the light slow-down factor on the mode field overlap with the silicon region, as well as on the complex effective nonlinear susceptibility. It is found that slotted photonic crystal modes tend to focalize in their hollow core with increasing group index(n_G) values. Considering a hybrid integration of nonlinear polymers in such slotted waveguides, a relative decrease of the TPA process by more factor of 2 is predicted from n_G=10 to n_G=50. As a whole, this work shows that the relative influence of TPA decreases for slotted waveguides operating in the slow light regime, making them a suitable platform for third-order nonlinear optics.展开更多
Ferroelectric domain engineering with infrared femtosecond laser pulses has been a powerful technique to achieve a spatially modulated second-order nonlinear coefficient in three dimensions.However,studies regarding t...Ferroelectric domain engineering with infrared femtosecond laser pulses has been a powerful technique to achieve a spatially modulated second-order nonlinear coefficient in three dimensions.However,studies regarding the in-fluence of laser writing conditions on the light-induced ferroelectric domain inversion remain limited.Herein,an experimental study to reveal the role of laser polarization in light-induced domain inversions is discussed.The dependence of the optical threshold and maximal writing depth of inverted domains on light polarization is ex-perimentally investigated.The results are explained by considering the second-order nonlinear optical properties and birefringence-induced focus splitting in the crystal.These findings are useful in fabricating high-quality and large-scale ferroelectric domain structures for applications in optics,electronics,and quantum technologies.展开更多
The design of nonlinear photonic Vogel's spiral based on quasi-crystal theory was demonstrated.Two main parameters of Vogel's spiral were arranged to obtain multi-reciprocal circles.Typical structure was fabri...The design of nonlinear photonic Vogel's spiral based on quasi-crystal theory was demonstrated.Two main parameters of Vogel's spiral were arranged to obtain multi-reciprocal circles.Typical structure was fabricated by the near-infrared femtosecond laser poling technique,forming a nonlinear photonic structure,and multiple ring-like nonlinear Raman±Nath second-harmonic generation processes were realized and analyzed in detail.The structure for the cascaded thirdharmonic generation process was predicted.The results could help deepen the understanding of Vogel's spiral and quasi-crystal and pave the way for the combination of quasi-crystal theory with more aperiodic structures.展开更多
In this paper,we have proposed and demonstrated the generation of passively mode-locked pulses and dissipative soliton resonance in an erbium-doped fiber laser based on Fe3O4 nanoparticles as saturable absorbers.We ob...In this paper,we have proposed and demonstrated the generation of passively mode-locked pulses and dissipative soliton resonance in an erbium-doped fiber laser based on Fe3O4 nanoparticles as saturable absorbers.We obtained self-starting mode-locked pulses with fundamental repetition frequency of 7.69 MHz and center wavelength of 1561 nm.The output of a pulsed laser has spectral width of 0.69 nm and pulse duration of 14 ns with rectangular pulse profile at the pump power of 190 mW.As far as we know,this is the first time that Fe3O4 nanoparticles have been developed as low-dimensional materials for passive mode-locking with rectangular pulse.Our experiments have confirmed that Fe3O4 has a wide prospect as a nonlinear photonics device for ultrafast fiber laser applications.展开更多
Three-dimensional(3D) nonlinear photonic crystals have received intensive interest as an ideal platform to study nonlinear wave interactions and explore their applications. Periodic fork-shaped gratings are extremely ...Three-dimensional(3D) nonlinear photonic crystals have received intensive interest as an ideal platform to study nonlinear wave interactions and explore their applications. Periodic fork-shaped gratings are extremely important in this context because they are capable of generating second-harmonic vortex beams from a fundamental Gaussian wave, which has versatile applications in optical trapping and materials engineering. However, previous studies mainly focused on the normal incidence of the fundamental Gaussian beam, resulting in symmetric emissions of the second-harmonic vortices. Here we present an experimental study on second-harmonic vortex generation in periodic fork-shaped gratings at oblique incidence, in comparison with the case of normal incidence. More quasi-phase-matching resonant wavelengths have been observed at oblique incidence, and the second-harmonic emissions become asymmetric against the incident beam.These results agree well with theoretic explanations. The oblique incidence of the fundamental wave is also used for the generation of second-harmonic Bessel beams with uniform azimuthal intensity distributions. Our study is important for a deeper understanding of nonlinear interactions in a 3D periodic medium. It also paves the way toward achieving highquality structured beams at new frequencies, which is important for manipulation of the orbital angular momentum of light.展开更多
基金National Natural Science Foundation of China(NSFC)(11374263,61422510,61431166001,61725503)Natural Science Foundation of Zhejiang Province(Z18F050002)National Major Research and Development Program(2016YFB0402502)
文摘Nonlinear silicon photonics has shown an ability to generate, manipulate, and detect optical signals on an ultracompact chip at a potential low cost. There are still barriers hindering its development due to essential material limitations. In this review, hybrid structures with some specific materials developed for nonlinear silicon photonics are discussed. The combination of silicon and the nonlinear materials takes advantage of both materials, which shows great potential to improve the performance and expand the applications for nonlinear silicon photonics.
基金Project supported by the Key-Area Research and Development Program of Guangdong Province of China (Grant No.2018B030325002)the National Natural Science Foundation of China (Grant No.62075129)+2 种基金the Open Project Program of SJTU-Pinghu Institute of Intelligent Optoelectronics (Grant No.2022SPIOE204)the Science and Technology on Metrology and Calibration Laboratory (Grant No.JLJK2022001B002)the Sichuan Provincial Key Laboratory of Microwave Photonics (Grant No.2023-04)。
文摘Hyperentanglement is a promising resource for achieving high capacity quantum communication.Here,we propose a compact scheme for the generation of path-frequency hyperentangled photon pairs via spontaneous parametric down-conversion(SPDC)processes,where six different paths and two different frequencies are covered.A two-dimensional periodicalχ^((2))nonlinear photonic crystal(NPC)is designed to satisfy type-Ⅰquasi-phase-matching conditions in the plane perpendicular to the incident pump beam,and a perfect phase match is achieved along the pump beam's direction to ensure high conversion efficiency,with theoretically estimated photon flux up to 2.068×10^(5) pairs·s^(-1)·mm^(-2).We theoretically calculate the joint-spectral amplitude(JSA)of the generated photon pair and perform Schmidt decomposition on it,where the resulting entropy S of entanglement and effective Schmidt rank K reach 3.2789 and 6.4675,respectively.Our hyperentangled photon source scheme could provide new avenues for high-dimensional quantum communication and high-speed quantum information processing.
基金the Key-Area Research and Development Program of Guangdong Province of China(Grant No.2018B030325002)the National Natural Science Foundation of China(Grant No.62075129)+1 种基金the Open Project Program of SJTU-Pinghu Institute of Intelligent Optoelectronics(Grant No.2022SPIOE204)the Science and Technology on Metrology and Calibration Laboratory(Grant No.JLJK2022001B002)。
文摘Generation of hyperentangled photon pairs is investigated based on the lithium niobate straight waveguide.We propose to use the nonlinear optical process of spontaneous parametric down-conversion(SPDC)and a well-designed lithium niobate waveguide structure to generate a hyperentangled(in the polarization dimension and the energy-time dimension)two-photon state.By performing numerical simulations of the waveguide structure and calculating the possible polarization states,joint spectral amplitudes(JSA),and joint temporal amplitudes(JTA)of the generated photon pair,we show that the generated photon pair is indeed hyperentangled in both the polarization dimension and the energy-time dimension.
基金“Investissements d’Avenir”program,French Agence Nationale de la Recherche(ANR)(ANR-10-LABX-0035)through the contact“CONDOR”French RENATECH NetworkIDEX AAP IDI 2013(37-2013)
文摘We introduce a nanoscale photonic platform based on gallium phosphide. Owing to the favorable material properties, peak power intensity levels of 50 GW∕cm^2 are safely reached in a suspended membrane. Consequently,the field enhancement is exploited to a far greater extent to achieve efficient and strong light–matter interaction.As an example, parametric interactions are shown to reach a deeply nonlinear regime, revealing cascaded fourwave mixing leading to comb generation and high-order soliton dynamics.
文摘The field of nonlinear photonics is in full development. This special issue of Photonics Research takes you through the current issues of this fast-growing field of research, drawing on the current state of the art and seeking, through a selection of articles, to outline some trends for the future.
基金supported by the National Natural Science Foundation of China(No.11004175)the Communication University of China(Nos.3132016XNG1616and YXJS201306)support of the Air Force Office of Scientific Research(AFOSR),USA Grant nos.FA9550-12-1-0454 and FA9550-16-1-0069
文摘Five conical harmonic beams are generated from the interaction of femtosecond mid-infrared(mid-IR) pulses at a nominal input wavelength of 1997 nm with a 2D LiNbO_3 nonlinear photonic crystal with Sierpinski fractal superlattices. The main diffraction orders and the corresponding reciprocal vectors involved in the interaction are ascertained. Second and third harmonics emerging at external angles of 23.82° and 36.75° result from nonlinearerenkov and Bragg diffractions, respectively. Three pathways of fourth-harmonic generation are observed at external angles of 14.21°, 36.5°, and 53.48°, with the first one resulting from nonlinearerenkov diffraction, and the other two harmonics are generated via different cascaded processes.
基金supported in part by the National Natural Science Foundation of China (Grant Nos. 11474108, 61378036, 61307058, 11304101, 11074078)the PhD Start-up Fund of Natural Science Foundation of Guangdong Province, China (Grant No. S2013040016320)+2 种基金the Scientific and Technological Innovation Project of Higher Education Institute, Guangdong, China (Grant No. 2013KJCX0051)the financial support from the Guangdong Natural Science Funds for Distinguished Young Scholarthe Zhujiang New-star Plan of Science & Technology in Guangzhou City (Grant No. 2014J2200008)
文摘Two-dimensional(2D) materials have emerged as attractive mediums for fabricating versatile optoelectronic devices. Recently, few-layer molybdenum disulfide(MoS2), as a shining 2D material, has been discovered to possess both the saturable absorption effect and large nonlinear refractive index. Herein, taking advantage of the unique nonlinear optical properties of MoS2, we fabricated a highly nonlinear saturable absorption photonic device by depositing the few-layer MoS2 onto the microfiber. With the proposed MoS2 photonic device, apart from the conventional soliton patterns, the mode-locked pulses could be shaped into some new soliton patterns, namely,multiple soliton molecules, localized chaotic multipulses, and double-scale soliton clusters. Our findings indicate that the few-layer MoS2-deposited microfiber could operate as a promising highlynonlinear photonic device for the related nonlinear optics applications.
基金supported by the National Natural Science Foundation of China(Nos.61905124,11974196,and 61905125)the Australian Research Council(No.DP19010774)+2 种基金the Qatar National Research Fund(No.NPRP 12S-0205190047)the Yongjiang Scholar Foundation of Ningbothe K.C.Wong Magna Fund of Ningbo University。
文摘The nonlinear Talbot effect is a near-field nonlinear diffraction phenomenon in which the self-imaging of periodic objects is formed by the second harmonics of the incident laser beam. We demonstrate the first, to the best of our knowledge, example of nonlinear Talbot self-healing, i.e., the capability of creating defect-free images from faulty nonlinear optical structures. In particular, we employ the tightly focused femtosecond infrared optical pulses to fabricate LiNbO_(3) nonlinear photonic crystals and show that the defects in the form of the missing points of two-dimensional square and hexagonal periodic structures are restored in the second harmonic images at the first nonlinear Talbot plane. The observed nonlinear Talbot self-healing opens up new possibilities for defect-tolerant optical lithography and printing.
文摘We investigate in this paper the influence of slow light on the balance between the Kerr and two-photon absorption(TPA) processes in silicon slotted hybrid nonlinear waveguides. Three typical silicon photonic waveguide geometries are studied to estimate the influence of the light slow-down factor on the mode field overlap with the silicon region, as well as on the complex effective nonlinear susceptibility. It is found that slotted photonic crystal modes tend to focalize in their hollow core with increasing group index(n_G) values. Considering a hybrid integration of nonlinear polymers in such slotted waveguides, a relative decrease of the TPA process by more factor of 2 is predicted from n_G=10 to n_G=50. As a whole, this work shows that the relative influence of TPA decreases for slotted waveguides operating in the slow light regime, making them a suitable platform for third-order nonlinear optics.
基金This work was supported by the Australian Research CouncilNational Natural Science Foundation of China under Grant Nos.11974196,12274248,61905124,61905125,12174222+2 种基金YongjiangScholar Foundation of NingboK C Wong Magna Fund of Ningbo Uni-versityQatar National Research Fund(NPRP12S-0205-190047).
文摘Ferroelectric domain engineering with infrared femtosecond laser pulses has been a powerful technique to achieve a spatially modulated second-order nonlinear coefficient in three dimensions.However,studies regarding the in-fluence of laser writing conditions on the light-induced ferroelectric domain inversion remain limited.Herein,an experimental study to reveal the role of laser polarization in light-induced domain inversions is discussed.The dependence of the optical threshold and maximal writing depth of inverted domains on light polarization is ex-perimentally investigated.The results are explained by considering the second-order nonlinear optical properties and birefringence-induced focus splitting in the crystal.These findings are useful in fabricating high-quality and large-scale ferroelectric domain structures for applications in optics,electronics,and quantum technologies.
基金supported by the National Natural Science Foundation of China(Nos.62275136,61905124,12274248,and 62090063)the Natural Science Foundation of Zhejiang Province(No.LY22F050009)+1 种基金the Yongjiang Scholar Foundation of Ningbothe K.C.Wong Magna Fund of Ningbo University。
文摘The design of nonlinear photonic Vogel's spiral based on quasi-crystal theory was demonstrated.Two main parameters of Vogel's spiral were arranged to obtain multi-reciprocal circles.Typical structure was fabricated by the near-infrared femtosecond laser poling technique,forming a nonlinear photonic structure,and multiple ring-like nonlinear Raman±Nath second-harmonic generation processes were realized and analyzed in detail.The structure for the cascaded thirdharmonic generation process was predicted.The results could help deepen the understanding of Vogel's spiral and quasi-crystal and pave the way for the combination of quasi-crystal theory with more aperiodic structures.
基金supported by the National Natural Science Foundation of China(Grant No.61605106)Funded projects for the Academic Leader and Academic Backbones,Shaanxi Normal University(No.18QNGG006)+3 种基金Shaanxi International Cooperation Project(No.2020KW-005)Starting Grants of Shaanxi Normal University(Nos.1112010209 and 1110010717)Open Research Fund of State Key Laboratory of Transient Optics and Photonics,Chinese Academy of Sciences(No.SKLST201809)Fundamental Research Funds for the Central Universities(Nos.GK201802006 and 2018CSLY005).
文摘In this paper,we have proposed and demonstrated the generation of passively mode-locked pulses and dissipative soliton resonance in an erbium-doped fiber laser based on Fe3O4 nanoparticles as saturable absorbers.We obtained self-starting mode-locked pulses with fundamental repetition frequency of 7.69 MHz and center wavelength of 1561 nm.The output of a pulsed laser has spectral width of 0.69 nm and pulse duration of 14 ns with rectangular pulse profile at the pump power of 190 mW.As far as we know,this is the first time that Fe3O4 nanoparticles have been developed as low-dimensional materials for passive mode-locking with rectangular pulse.Our experiments have confirmed that Fe3O4 has a wide prospect as a nonlinear photonics device for ultrafast fiber laser applications.
基金supported by the National Natural Science Foundation of China (Nos. 12274248, 62275136, 61905124,and 61905125)the Natural Science Foundation of Zhejiang Province (No. LY22F050009)+1 种基金the Australian Research Councilthe K.C.Wong Magna Fund of Ningbo University。
文摘Three-dimensional(3D) nonlinear photonic crystals have received intensive interest as an ideal platform to study nonlinear wave interactions and explore their applications. Periodic fork-shaped gratings are extremely important in this context because they are capable of generating second-harmonic vortex beams from a fundamental Gaussian wave, which has versatile applications in optical trapping and materials engineering. However, previous studies mainly focused on the normal incidence of the fundamental Gaussian beam, resulting in symmetric emissions of the second-harmonic vortices. Here we present an experimental study on second-harmonic vortex generation in periodic fork-shaped gratings at oblique incidence, in comparison with the case of normal incidence. More quasi-phase-matching resonant wavelengths have been observed at oblique incidence, and the second-harmonic emissions become asymmetric against the incident beam.These results agree well with theoretic explanations. The oblique incidence of the fundamental wave is also used for the generation of second-harmonic Bessel beams with uniform azimuthal intensity distributions. Our study is important for a deeper understanding of nonlinear interactions in a 3D periodic medium. It also paves the way toward achieving highquality structured beams at new frequencies, which is important for manipulation of the orbital angular momentum of light.