Nonlinear optics(NLO)of transition metal dichalcogenides(TMDs)is promising for the on-chip photonic and optoelectronic applications.In this review,we will survey the current progress of NLO in TMDs.First,we will brief...Nonlinear optics(NLO)of transition metal dichalcogenides(TMDs)is promising for the on-chip photonic and optoelectronic applications.In this review,we will survey the current progress of NLO in TMDs.First,we will brief the basic theory of the NLO in TMDs.Second,several important nonlinear processes in TMDs such as harmonic generation,four-wave mixing,saturable absorption,and two-photon absorption will be presented and their potential applications are also discussed.Third,the main strategies to tune,modulate,and enhance the NLO in TMDs are reviewed,including the excitonic effect,symmetry modulation,optical cavity enhancement,valley selection,edge state,and material phase.Finally,we give an outlook regarding some important issues and directions of NLO in TMDs.展开更多
An NLO hyperbranched polymer (HP1) derived from both "H"-type and star-type chromophores was synthesized successfully for the first time with high yield via one-pot "A2 + B3" Suzuki polymerization reaction. Iso...An NLO hyperbranched polymer (HP1) derived from both "H"-type and star-type chromophores was synthesized successfully for the first time with high yield via one-pot "A2 + B3" Suzuki polymerization reaction. Isolation chromophore was also introduced to further improve its performance. Although under the test conditions, the films of HP1 could not be poled completely, it still demonstrated satisfactory macroscopic NLO effect with the second harmonic generation (SHG) coefficient d33 value of 36 pm/V.展开更多
A series of new stable (thermal and photochemical) ferrocenyl derivatives containing C=N bond and benzene ring in long conjugated chains have been synthesized and characterized by (HNMR)-H-1(400MHz), IR, and elemental...A series of new stable (thermal and photochemical) ferrocenyl derivatives containing C=N bond and benzene ring in long conjugated chains have been synthesized and characterized by (HNMR)-H-1(400MHz), IR, and elemental analysis. Pull-push ferrocenyl complexes that we have prepared have strong NLO responses identified by electronic absorption spectrum.展开更多
The structures,electronic spectra,polarizability and third-order nonlinear optical properties of six gold compounds [X-{Au(PMe3)}2]were investigated by density functional theory(DFT)B3LYP and BhandHLYP methods.It was ...The structures,electronic spectra,polarizability and third-order nonlinear optical properties of six gold compounds [X-{Au(PMe3)}2]were investigated by density functional theory(DFT)B3LYP and BhandHLYP methods.It was found that the calculation methods and basis set are rational for the object of study,and molecular structures change slightly when PPh3 is replaced by PMe3.The spatial effects of the bridging section have a significant influence on the polarizability,but indistinctive to the third-order nonlinear optical(NLO)coefficient.As a result of the conjugated effect in different compounds,the third-order polarizability of molecule 1a is the smallest,while that of molecule 2a is the largest.Au has donor ability in molecule 1a but acceptor ability in molecules 2a-6a by analyzing the electronic spectra and frontier molecular orbitals constitute maximal absorption,which indicates the contribution of Au to NLO properties in the six molecules is different.展开更多
The nonlinear optical (NLO) and optical limiting (OL) properties of three new structures of organic NLO guest host Poly(N-vinylcarbozole)/disperse orange 3 (PVK/DO3), PVK/disperse orange 13 (PVK/DO13). and P...The nonlinear optical (NLO) and optical limiting (OL) properties of three new structures of organic NLO guest host Poly(N-vinylcarbozole)/disperse orange 3 (PVK/DO3), PVK/disperse orange 13 (PVK/DO13). and PVK/disperse orange 25 (PVK/DO25) as a solution at different concentrations and as a thin-film sample are studied using continuous wave z-scan system at 532 nm. The open-aperture z-scan data of the NLO materials in the solution and thin-film samples displayed two-photon and saturable absorptions, respectively. The PVK/DO13 exhibites the largest and best values of the nonlinearities, such as n2, β, X(3) compared with those of PVK/DO3 and PVK/DO25. This nonlinearity increases as the concentration increases. Tile results indicate that these NLO materials are good candidates for optical switching and OL devices.展开更多
In recent years, motivated by the discovery of deep-UV(wavelengths below 200 nm) nonlinear optical(NLO) phosphates, Ba3P3O(10)X(Cl, Br), phosphates have entered into a passionate research era. In this review, ...In recent years, motivated by the discovery of deep-UV(wavelengths below 200 nm) nonlinear optical(NLO) phosphates, Ba3P3O(10)X(Cl, Br), phosphates have entered into a passionate research era. In this review, recently discovered phosphate materials containing different anionic groups, i.e., isolated [PO4], [P2O7] dimer, [P3O(10)] trimer, and [PO3]∞ chain, are summarized, including their syntheses, structures, NLO performances and properties. Especially phosphates with short absorption edges in the deep-UV region and good SHG efficiency are introduced in detail. We hope that this work will present a clear view of the crystal chemistry of phosphates and promote the discovery of new high-performing second-order NLO materials to meet the urgent needs in laser science.展开更多
A new tetranuclear cyanide-bridged complex [PPh4]2[NiⅡ(CN)4CuⅠ(PPh3)2]2·2CH3OH ([PPh4]+ = tetraphenylphosphine cation, PPh3 = triphenylphosphine) 1 has been synthesized and characterized by IR spectrosco...A new tetranuclear cyanide-bridged complex [PPh4]2[NiⅡ(CN)4CuⅠ(PPh3)2]2·2CH3OH ([PPh4]+ = tetraphenylphosphine cation, PPh3 = triphenylphosphine) 1 has been synthesized and characterized by IR spectroscopy, elemental analysis, electronic absorption spectra and single-crystal X-ray diffraction. This complex crystallizes in triclinic, space group Pí with a = 10.910(5), b = 15.777(7), c = 18.275(8), α = 68.752(12), β = 79.776(13), γ = 81.400(14)°, NiCuC65H50N4OP3, Mr = 1122.25, V = 2873(2)3 , Z = 2, Dc = 1.293 g/cm3, F(000) = 1156, μ = 0.826 mm-1, the final R = 0.0755 and wR = 0.2155 for 7324 observed reflections (I 2σ(I)). The title compound exhibits a discrete square tetranuclear structure and a cubic order NLO property.展开更多
A new non-metal 3-D borophosphate compound formulated as(NH4)2[B2P2O8(OH)2](1)has been synthesized by a solvothermal method and characterized by elemental analysis,energy-dispersive X-ray spectroscopy(EDS),IR spectrum...A new non-metal 3-D borophosphate compound formulated as(NH4)2[B2P2O8(OH)2](1)has been synthesized by a solvothermal method and characterized by elemental analysis,energy-dispersive X-ray spectroscopy(EDS),IR spectrum and single-crystal X-ray diffraction.The borophosphate(NH4)2[B2P2O8(OH)2]crystallizes in the cubic system,space group P213 with Z=2,a=b=c=7.586(4)?,V=436.6(4)?3,Mr=281.64,Dc=2.127 g/cm^3,λ=0.71073?,μ=0.551 mm^-1,F(000)=284,R=0.0277 and wR=0.0758 for 262 observed reflections with I>2σ(I)and S=1.082.Its structure is constructed by the connection of PO4 and BO3(OH)tetrahedra to form a 3-D anionic framework containing 4-and 8-membered rings(MRs),with two NH4+cations located in the channels of the 8-membered rings.The N–H…O hydrogen bonds are observed in its packing structure and enhanced the stability of crystal structure.In addition,its thermal stability,UV spectrum and second-order NLO properties have been also investigated.展开更多
The geometrical structures and stability of non-conjugated C5H10 and C3H8N2 singlet and triplet diradical molecules have been investigated at the UCCSD/6-311g^** level. The effects of molecular structure, radical po...The geometrical structures and stability of non-conjugated C5H10 and C3H8N2 singlet and triplet diradical molecules have been investigated at the UCCSD/6-311g^** level. The effects of molecular structure, radical position, amount of Hartree Hork (HF) exchange and spin multiplicity on the nonlinear optical (NLO) coefficients have been also investigated. The reliable UCCSD results show that the triplets of all diradical molecules are more stable compared to their singlet analogues. In addition, the αs and βtot values of C5H10 and C3H8N2 triplet diradical mo-lecules have been investigated by the UBHandHLYP, UB3LYP, UBLYP, UHF and UCCSD methods. The investigation shows that the variations in αs and βtot values are closely connected to the amount of HF exchange. The increasing amount of HF exchange results in monotonic decreases in αs and βtot values, while the αs and βtot values of singlet diradical molecules and the γs of C5H10 and C3H8N2 singlet and triplet diradical molecules have been studied by the UBHandHLYP method. The results illustrate that the NLO coefficients for our studied non-conjugated carbon and nitrogen diradical species can be tuned by molecular structure, radical position and spin multiplicity, which are very significant for designing NLO materials.展开更多
Non-centrosymmetric(NCS)structure is an indispensable prerequisite for second-order nonlinear optical(NLO)material.Currently,the mainstream approach for designing new NCS structures still relies on chemical substituti...Non-centrosymmetric(NCS)structure is an indispensable prerequisite for second-order nonlinear optical(NLO)material.Currently,the mainstream approach for designing new NCS structures still relies on chemical substitution,necessitating an urgent infusion of fresh ideas.In this work,two isomorphic sulfides AeMn_(6)Ga_(6)S_(16)(Ae=Ca,1;Sr,2)are afforded by modifying the skeleton of centrosymmetric(CS)Mn_(2)Ga_(2)S_(5) via introducing strong electropositive alkaline-earth cations.Concretely,the incorporation of Ca^(2+)/Sr^(2+)cations allows the elementary[MnGaS_(9)]_(∞)chains to reconfigure into bumpy[MnS_(6)]-[GaS_(4)]layers in a new engagement manner,thus enabling the conversion from CS to NCS structure.Such modifications cause not only strong second-harmonic generation(SHG)responses(~1.5×benchmark AgGaS_(2)@1,700 nm),but also significantly feasible bandgaps(2.60-2.64 e V)compared to the sulfide Mn_(2)Ga_(2)S_(5)(1.36 e V),which ultimately facilitate ultrahigh laser-induced damage thresholds(4.4-6.6×AgGaS_(2)@1,064 nm for compounds 1 and 2).The present study offers an ingenious approach for the transformation of CS to NCS structure.展开更多
The external electric field is a special strategy for generating novel structures.In this work,the intermolecular bonding and nonlinear optical properties are affected by applying an applied electric field of 0 to 9.7...The external electric field is a special strategy for generating novel structures.In this work,the intermolecular bonding and nonlinear optical properties are affected by applying an applied electric field of 0 to 9.77 V·nm^(-1)along the bonding direction of dimer of olympicenyl radical(OLY2).The results showed that the distance between molecular layers was lengthened gradually,and the 2e/20c bonds were weakened or even completely broken(the critical electric field is 9.77 V·nm^(-1))with the increase of the external electric field strength.Moreover,the introduction of an external electric field caused significant changes in the electronic properties of the OLY2,which induced charge transfer between inter-layer monomers,and enhanced the interlayer electrostatic interactions.Therefore,the external electric field not only regulates the interlayer interactions of molecules,but also causes the symmetric molecules to produce strong polarity,producing a large NLO response in OLY2.展开更多
基金support from National Natural Science Foundation of China(Grant no.61674060)the Fundamental Research Funds for the Central Universities,Huazhong University of Science and Technology(Grant no.2019kfyXJJS046,2017KFYXJJ030,2017KFXKJ003,2017KFXKJC002).
文摘Nonlinear optics(NLO)of transition metal dichalcogenides(TMDs)is promising for the on-chip photonic and optoelectronic applications.In this review,we will survey the current progress of NLO in TMDs.First,we will brief the basic theory of the NLO in TMDs.Second,several important nonlinear processes in TMDs such as harmonic generation,four-wave mixing,saturable absorption,and two-photon absorption will be presented and their potential applications are also discussed.Third,the main strategies to tune,modulate,and enhance the NLO in TMDs are reviewed,including the excitonic effect,symmetry modulation,optical cavity enhancement,valley selection,edge state,and material phase.Finally,we give an outlook regarding some important issues and directions of NLO in TMDs.
基金supported by the National Natural Science Foundation of China(No.21034006)
文摘An NLO hyperbranched polymer (HP1) derived from both "H"-type and star-type chromophores was synthesized successfully for the first time with high yield via one-pot "A2 + B3" Suzuki polymerization reaction. Isolation chromophore was also introduced to further improve its performance. Although under the test conditions, the films of HP1 could not be poled completely, it still demonstrated satisfactory macroscopic NLO effect with the second harmonic generation (SHG) coefficient d33 value of 36 pm/V.
文摘A series of new stable (thermal and photochemical) ferrocenyl derivatives containing C=N bond and benzene ring in long conjugated chains have been synthesized and characterized by (HNMR)-H-1(400MHz), IR, and elemental analysis. Pull-push ferrocenyl complexes that we have prepared have strong NLO responses identified by electronic absorption spectrum.
基金supported by the National Natural Science Foundation of China(20873017)Program for Changjiang Scholars and Innovative Research Team in University(IRT0714)
文摘The structures,electronic spectra,polarizability and third-order nonlinear optical properties of six gold compounds [X-{Au(PMe3)}2]were investigated by density functional theory(DFT)B3LYP and BhandHLYP methods.It was found that the calculation methods and basis set are rational for the object of study,and molecular structures change slightly when PPh3 is replaced by PMe3.The spatial effects of the bridging section have a significant influence on the polarizability,but indistinctive to the third-order nonlinear optical(NLO)coefficient.As a result of the conjugated effect in different compounds,the third-order polarizability of molecule 1a is the smallest,while that of molecule 2a is the largest.Au has donor ability in molecule 1a but acceptor ability in molecules 2a-6a by analyzing the electronic spectra and frontier molecular orbitals constitute maximal absorption,which indicates the contribution of Au to NLO properties in the six molecules is different.
文摘The nonlinear optical (NLO) and optical limiting (OL) properties of three new structures of organic NLO guest host Poly(N-vinylcarbozole)/disperse orange 3 (PVK/DO3), PVK/disperse orange 13 (PVK/DO13). and PVK/disperse orange 25 (PVK/DO25) as a solution at different concentrations and as a thin-film sample are studied using continuous wave z-scan system at 532 nm. The open-aperture z-scan data of the NLO materials in the solution and thin-film samples displayed two-photon and saturable absorptions, respectively. The PVK/DO13 exhibites the largest and best values of the nonlinearities, such as n2, β, X(3) compared with those of PVK/DO3 and PVK/DO25. This nonlinearity increases as the concentration increases. Tile results indicate that these NLO materials are good candidates for optical switching and OL devices.
基金supported by the National Natural Science Foundation of China under Projects 91422303,21571020,and 21671023
文摘In recent years, motivated by the discovery of deep-UV(wavelengths below 200 nm) nonlinear optical(NLO) phosphates, Ba3P3O(10)X(Cl, Br), phosphates have entered into a passionate research era. In this review, recently discovered phosphate materials containing different anionic groups, i.e., isolated [PO4], [P2O7] dimer, [P3O(10)] trimer, and [PO3]∞ chain, are summarized, including their syntheses, structures, NLO performances and properties. Especially phosphates with short absorption edges in the deep-UV region and good SHG efficiency are introduced in detail. We hope that this work will present a clear view of the crystal chemistry of phosphates and promote the discovery of new high-performing second-order NLO materials to meet the urgent needs in laser science.
基金supported by grants from the 973 Program(2012CB821700)the National Natural Science Foundation of China(21073192,20871114 and 21173223)the Science Foundation of CAS(KJCX2-YW-H20)and of Fujian Province(2009HZ0006-1)
文摘A new tetranuclear cyanide-bridged complex [PPh4]2[NiⅡ(CN)4CuⅠ(PPh3)2]2·2CH3OH ([PPh4]+ = tetraphenylphosphine cation, PPh3 = triphenylphosphine) 1 has been synthesized and characterized by IR spectroscopy, elemental analysis, electronic absorption spectra and single-crystal X-ray diffraction. This complex crystallizes in triclinic, space group Pí with a = 10.910(5), b = 15.777(7), c = 18.275(8), α = 68.752(12), β = 79.776(13), γ = 81.400(14)°, NiCuC65H50N4OP3, Mr = 1122.25, V = 2873(2)3 , Z = 2, Dc = 1.293 g/cm3, F(000) = 1156, μ = 0.826 mm-1, the final R = 0.0755 and wR = 0.2155 for 7324 observed reflections (I 2σ(I)). The title compound exhibits a discrete square tetranuclear structure and a cubic order NLO property.
基金Supported by the National Natural Science Foundation of China(No.21601095)
文摘A new non-metal 3-D borophosphate compound formulated as(NH4)2[B2P2O8(OH)2](1)has been synthesized by a solvothermal method and characterized by elemental analysis,energy-dispersive X-ray spectroscopy(EDS),IR spectrum and single-crystal X-ray diffraction.The borophosphate(NH4)2[B2P2O8(OH)2]crystallizes in the cubic system,space group P213 with Z=2,a=b=c=7.586(4)?,V=436.6(4)?3,Mr=281.64,Dc=2.127 g/cm^3,λ=0.71073?,μ=0.551 mm^-1,F(000)=284,R=0.0277 and wR=0.0758 for 262 observed reflections with I>2σ(I)and S=1.082.Its structure is constructed by the connection of PO4 and BO3(OH)tetrahedra to form a 3-D anionic framework containing 4-and 8-membered rings(MRs),with two NH4+cations located in the channels of the 8-membered rings.The N–H…O hydrogen bonds are observed in its packing structure and enhanced the stability of crystal structure.In addition,its thermal stability,UV spectrum and second-order NLO properties have been also investigated.
基金Supported by the National Natural Science Foundation of China (20873017)the Natural Science Foundation of Jilin Province (20101154)
文摘The geometrical structures and stability of non-conjugated C5H10 and C3H8N2 singlet and triplet diradical molecules have been investigated at the UCCSD/6-311g^** level. The effects of molecular structure, radical position, amount of Hartree Hork (HF) exchange and spin multiplicity on the nonlinear optical (NLO) coefficients have been also investigated. The reliable UCCSD results show that the triplets of all diradical molecules are more stable compared to their singlet analogues. In addition, the αs and βtot values of C5H10 and C3H8N2 triplet diradical mo-lecules have been investigated by the UBHandHLYP, UB3LYP, UBLYP, UHF and UCCSD methods. The investigation shows that the variations in αs and βtot values are closely connected to the amount of HF exchange. The increasing amount of HF exchange results in monotonic decreases in αs and βtot values, while the αs and βtot values of singlet diradical molecules and the γs of C5H10 and C3H8N2 singlet and triplet diradical molecules have been studied by the UBHandHLYP method. The results illustrate that the NLO coefficients for our studied non-conjugated carbon and nitrogen diradical species can be tuned by molecular structure, radical position and spin multiplicity, which are very significant for designing NLO materials.
基金supported by the National Natural Science Foundation of China(21827813,21921001,22175172,22075283,92161125,U21A20508)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2020303,2021300)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2020ZZ108)。
文摘Non-centrosymmetric(NCS)structure is an indispensable prerequisite for second-order nonlinear optical(NLO)material.Currently,the mainstream approach for designing new NCS structures still relies on chemical substitution,necessitating an urgent infusion of fresh ideas.In this work,two isomorphic sulfides AeMn_(6)Ga_(6)S_(16)(Ae=Ca,1;Sr,2)are afforded by modifying the skeleton of centrosymmetric(CS)Mn_(2)Ga_(2)S_(5) via introducing strong electropositive alkaline-earth cations.Concretely,the incorporation of Ca^(2+)/Sr^(2+)cations allows the elementary[MnGaS_(9)]_(∞)chains to reconfigure into bumpy[MnS_(6)]-[GaS_(4)]layers in a new engagement manner,thus enabling the conversion from CS to NCS structure.Such modifications cause not only strong second-harmonic generation(SHG)responses(~1.5×benchmark AgGaS_(2)@1,700 nm),but also significantly feasible bandgaps(2.60-2.64 e V)compared to the sulfide Mn_(2)Ga_(2)S_(5)(1.36 e V),which ultimately facilitate ultrahigh laser-induced damage thresholds(4.4-6.6×AgGaS_(2)@1,064 nm for compounds 1 and 2).The present study offers an ingenious approach for the transformation of CS to NCS structure.
基金Foundation of Science and Technology Department of Jilin Province(20230101043JC).
文摘The external electric field is a special strategy for generating novel structures.In this work,the intermolecular bonding and nonlinear optical properties are affected by applying an applied electric field of 0 to 9.77 V·nm^(-1)along the bonding direction of dimer of olympicenyl radical(OLY2).The results showed that the distance between molecular layers was lengthened gradually,and the 2e/20c bonds were weakened or even completely broken(the critical electric field is 9.77 V·nm^(-1))with the increase of the external electric field strength.Moreover,the introduction of an external electric field caused significant changes in the electronic properties of the OLY2,which induced charge transfer between inter-layer monomers,and enhanced the interlayer electrostatic interactions.Therefore,the external electric field not only regulates the interlayer interactions of molecules,but also causes the symmetric molecules to produce strong polarity,producing a large NLO response in OLY2.