Large crystal NPP-OTs has been obtained by growth from solution,its powder SHG efficiency is 1/3 of urea.It shows it is a new convenient approach to obtain organic second-order NLO crystal:the dipole-dipole interactio...Large crystal NPP-OTs has been obtained by growth from solution,its powder SHG efficiency is 1/3 of urea.It shows it is a new convenient approach to obtain organic second-order NLO crystal:the dipole-dipole interaction is oppos- ed by introducing a large side group.展开更多
The structure of ZnL2Cl2 (L=4-methoxybenzaldehyde thiosemicarbazone) has beenobtained by x-ray diffraction. The compound crystallized in space group Cc with Z=4, in a unit cellof dimensions, a=9.08909(10), b=22. l420(...The structure of ZnL2Cl2 (L=4-methoxybenzaldehyde thiosemicarbazone) has beenobtained by x-ray diffraction. The compound crystallized in space group Cc with Z=4, in a unit cellof dimensions, a=9.08909(10), b=22. l420(10), c=11 .7890(l0)A,β=90.050(10)°, v=2374.6(12)A3,Dc=1 .552gcm-3. H=1 .463mm-1. R=0.0338. and Rw=0.0418. The structure contains individualZnL2Cl2 distorted tetrahedral units in which L molecules are S-bonded as monodentate to the metalions; chloride ions are also coordinated. The nonlinear optical properties of the zinc complex arealso presented in this letter.展开更多
Nonlinear optical(NLO)materials play an increasingly important role in laser technology.Birefringence is one of the most important parameters for NLO materials to realize angle phase-matching conditions.In comparison ...Nonlinear optical(NLO)materials play an increasingly important role in laser technology.Birefringence is one of the most important parameters for NLO materials to realize angle phase-matching conditions.In comparison with other desirable optical properties,the availability of birefringence and refractive index dispersion is especially problematic owing to the strict requirements for single crystals.In this review,we described how to obtain the refractive index and birefringence of NLO materials from crystals sub-millimeters to centimeters in size.Espe-cially,recently developed methods including the minimum deflection angle method,auto-collimation method,prism coupling method,oil immersion technique,interference color method,and theoretical calculation(DFT)for rapid assessment of birefringence are summarized,the contents of which are mainly focused on the principles and typical applications,together with the advantages and drawbacks.In addition,representative examples of bire-fringent measurements were presented.The purpose of this work is to provide a useful perspective on the characterization of birefringence for NLO materials.It is hoped that this review can give a clear description of the birefringence measurements and accelerate the discovery of new NLO crystals.展开更多
A novel tolane 4-methoxy-4'-nitro-diphenyl-acetylene (MONA) has been prepared quantitatively by reacting cuprous p-methoxy phenyl-acetylene with p-iodonitrobenzene. A single crystal of the Moan was grown by soluti...A novel tolane 4-methoxy-4'-nitro-diphenyl-acetylene (MONA) has been prepared quantitatively by reacting cuprous p-methoxy phenyl-acetylene with p-iodonitrobenzene. A single crystal of the Moan was grown by solution growth method. The crystal was then characterized by X-ray diffraction structure analysis and second-harmonic generation(SHG)investigation. Polymorphous crystal forms of the MONA were grown from different solvents having different nonlinear optical properties depending on their different crystal structures. The relationship between the crystal growth and crystal structure is discusse.展开更多
Deep-ultraviolet(DUV)nonlinear optical(NLO)crystal is indispensable in current DUV all-solid-state laser technology,which is the key device to generate DUV light by frequency conversion.Due to stringent criteria,DUV N...Deep-ultraviolet(DUV)nonlinear optical(NLO)crystal is indispensable in current DUV all-solid-state laser technology,which is the key device to generate DUV light by frequency conversion.Due to stringent criteria,DUV NLO crystals are scarce and their discovery faces a big challenge.Although KBe2BO3F2(KBBF)is already excellent for current uses,the development of DUV science requires the materials with shorter output wavelengths and larger NLO effects,so as to meet the needs of DUV lasers with higher precision and higher power.Therefore,how to efficiently design DUV NLO materials has always been the core issue in NLO materials science.Looking back on the development of NLO materials,it turns out that theoretical modeling and simulation is an effective and efficient method,not only for mechanism understandings,but also for experimental exploration.In this article,in order to accelerate the process of DUV materials discovery,we summarize and propose a powerful computeraided modeling system and design blueprint that can be used to evaluate the DUV NLO performance in a faster way than pure experiments.With this in hand,we enrich the understanding of NLO structure-property correlation,and systematically prospect the DUV NLO properties on the basis of many existing and designed structures according to different structural types and chemical compositions.Seven novel structures are predicted for the first time to exhibit potential DUV NLO capabilities.All the results enable us to believe that the computer-aided modeling blueprint will play an important role in the exploration of new DUV NLO crystals.展开更多
zinc cadmium thiocyanate (ZCTC), ZnCd(SCN)_4, has been discoveredas a UV second-order nonlinear optical coordination crystal. Titsthermal and transmission Properties are reported. The thermaldecomposition is character...zinc cadmium thiocyanate (ZCTC), ZnCd(SCN)_4, has been discoveredas a UV second-order nonlinear optical coordination crystal. Titsthermal and transmission Properties are reported. The thermaldecomposition is characterized by using the X-ray Powder diffraction(XRPD) and infrared (IR) spectroscopy at room temperature. TheAbsorptions of intrinsic ions and ZCTC in a solution state arediscussed as well as Transmission properties of the ZCTC crystal. Aneffective method of reducing the surface Reflection loss of ZCTCcrystal is introduced.展开更多
UV nonlinear optical(NLO)crystals are essential materials for UV solid state laser output.To date,frequency conversion in UV region is mainly dependent on borates with planar BO3 or B3O6 units.Since the practical appl...UV nonlinear optical(NLO)crystals are essential materials for UV solid state laser output.To date,frequency conversion in UV region is mainly dependent on borates with planar BO3 or B3O6 units.Since the practical applications require more and more high comprehensive properties of crystals,it is urgent to develop new UV NLO crystals.However,it is more and more difficult to find new borate NLO crystals because borate NLO crystals have been studied for several decades.Therefore,it is important to search new systems for the exploration of UV NLO crystals.Based on the relationship between the microstructure and properties of the groups,we proposed that inorganic(CO3)2-and(NO3)-groups can be as new NLO active units for UV NLO crystals because they haveπ-conjugated configuration.Accordingly,our group have performed related work in carbonate and nitrate systems in recent years,which resulted in finding some excellent carbonates and nitrates NLO crystals.In addition,we have recently expanded the research field from inorganic to organicπ-conjugated systems,such as isocyanurates.This mini review will introduce the research results of our team in the field of UV NLO crystals including carbonates,nitrates and cyanurates in recent years.展开更多
The phase-matching for nonlinear optical crystal, the nonlinear phase matching angle, effective nonlinear coefficient, walk-off angles, permitted angle, and permitted wavelength are obtained in type-I and type-II phas...The phase-matching for nonlinear optical crystal, the nonlinear phase matching angle, effective nonlinear coefficient, walk-off angles, permitted angle, and permitted wavelength are obtained in type-I and type-II phase matching in ultraviolet （UV） nonlinear optical crystals CsLiB6O10 （CLBO） and K2Al2B2O7 （KABO） by detailed theoretical simulation. Through analysis and comparison, the phase matching characteristics of the second harmonic generation in the crystals are discussed when the wavelengths of the basic frequency lights turn continually.展开更多
Nonlinear optical(NLO)crystals have been playing an increasingly important role in laser science and technology.The NLO crystals used in the middle infrared(mid-IR)region,compared with the NLO crystals in the other wa...Nonlinear optical(NLO)crystals have been playing an increasingly important role in laser science and technology.The NLO crystals used in the middle infrared(mid-IR)region,compared with the NLO crystals in the other wavelength regions,are still not good enough for the application of high-energy laser.The main defect is that their laser damage thresholds(LDT)are low.Chinese scientists have made a lot of important contributions to the UV and visible NLO crystals.In the last decade,they also did a lot of work on the mid-IR NLO materials.The main purpose of these researches is to increase the LDT and simultaneously balance the other properties.This paper presents a brief summary of their research progress in this topic on three types of materials:chalcogenides,oxides,and halides.The emphasis is put on the design strategy and quality control of the crystals.展开更多
Benzoyl glycine （BG） is a promising organic nonlinear optical （NLO） crystal, whose second harmonic generation （SHG） efficiency is much higher than that of KDP （potassium dihydrogen phosphate）. Single crystals ...Benzoyl glycine （BG） is a promising organic nonlinear optical （NLO） crystal, whose second harmonic generation （SHG） efficiency is much higher than that of KDP （potassium dihydrogen phosphate）. Single crystals of pure, Cu2＋ and Cd2＋ doped BG were grown by slow evaporation technique. Optically transparent and defect free single crystals of size up to 10 mm×15 mm×10 mm were harvested in a period of 40-60 days. The growth conditions of pure and doped crystals of BG were optimized and the grown crystals were confirmed by single crystal XRD （X-ray diffraction）. The grown crystals were characterized by FTIR （Fourier transform infrared spectroscopy）, optical absorption and microhardness studies. The microhardness studies confirm that BG has a moderate VHN （Vickers hardness number） value in comparison to the.other organic NLO crystals. The efficiency of frequency doubling was measured for the using Nd：YAG laser and the results were discussed.展开更多
We report high-energy tunable 6.5-12 μm ps mid-infrared radiation generation based on OPA pumped using 1064 nm laser in LISe crystal.We simulated the relationship between the idler energy and crystal length.An optimu...We report high-energy tunable 6.5-12 μm ps mid-infrared radiation generation based on OPA pumped using 1064 nm laser in LISe crystal.We simulated the relationship between the idler energy and crystal length.An optimum LISe length of 4 mm was used to enhance the idler energy experimentally.At a pump energy of ~9.4 mJ, energy levels of ~146 and of ~27 μJ are generated at 6.5 μm and 12 μm, respectively.The highest energy of ~205 μJ is achieved at 8.1 μm at a pump energy of ~19 mJ.Finally, the angular and spectral width acceptance are measured.展开更多
In this study,the first methyl sulfonate deepultraviolet(DUV)nonlinear optical(NLO)crystal,Ba(SO_(3)CH_(3))_(2),was successfully synthesized with the polar non-π-conjugated tetrahedron,SO_(3)CH_(3)^(−),as a novel DUV...In this study,the first methyl sulfonate deepultraviolet(DUV)nonlinear optical(NLO)crystal,Ba(SO_(3)CH_(3))_(2),was successfully synthesized with the polar non-π-conjugated tetrahedron,SO_(3)CH_(3)^(−),as a novel DUV NLO building unit.Results showed that Ba(SO_(3)CH_(3))_(2)not only had a very short absorption edge of 159 nm,which is the shortest among reported phase-matchable sulfates or sulfonates,but also exhibited excellent optical properties.(Powder X-ray diffractionwas ca.1.5×KH_(2)PO_(4)and birefringence was 0.04 at 589.3 nm.)It also exhibited high thermal stability and remarkable stability against air and moisture.Additionally,bulk Ba(SO_(3)CH_(3))_(2)crystal could be obtained conveniently from a simple solution evaporation process.Therefore,Ba(SO_(3)CH_(3))_(2)should have great potential as a DUV NLO crystal in the near future.展开更多
Functional crystals are the basic materials for the development of modern science and technology and are playing key roles in the modern information era. In this paper, we review functional crystals in China, includin...Functional crystals are the basic materials for the development of modern science and technology and are playing key roles in the modern information era. In this paper, we review functional crystals in China, including research history, significant achievements, and important applications by highlighting the most recent progress in research. Challenges for the development of functional materials are discussed and possible directions for development are proposed by focusing on potential strengths of these materials.展开更多
The third harmonic generation（THG） of a linear cavity Ti：sapphire regenerative amplifier by use of a K3B6O（10）Cl（KBOC） crystal is studied for the first time. Output power up to 5.9 mW is obtained at a central w...The third harmonic generation（THG） of a linear cavity Ti：sapphire regenerative amplifier by use of a K3B6O（10）Cl（KBOC） crystal is studied for the first time. Output power up to 5.9 mW is obtained at a central wavelength of 263 nm,corresponding to a conversion efficiency of 4.5% to the second harmonic power. Our results show a tremendous potential for nonlinear frequency conversion into the deep ultraviolet range with the new crystal and the output laser power can be further improved.展开更多
K3B6O10Cl （KBOC）, a new nonlinear optical crystal, shows potential advantages for the generation of deep ultraviolet （UV） light compared with other borate crystals. In this paper we study for the first time the se...K3B6O10Cl （KBOC）, a new nonlinear optical crystal, shows potential advantages for the generation of deep ultraviolet （UV） light compared with other borate crystals. In this paper we study for the first time the second harmonic generation （SHG） of a femtosecond Ti：sapphire amplifier with this crystal. Laser power is obtained to be as high as 220 mW at the central wavelength of 396 nm with a 1-mm-long crystal, and the maximum SHG conversion efficiency reaches 39.3%. The typical pulse duration is 83 fs, The results show that second harmonic （SH） conversion efficiency has the room to be further improved and that the new nonlinear crystal is very suited to generate the high efficiency deep ultraviolet laser radiation below 266 nm.展开更多
High-efficiency single crystal cascaded third-harmonic generation(THG)was realized inβ-BaB_(2)O_(4)(BBO)material with special cut-angle.By analyzing effective nonlinear optical coefficient(d_(eff))of the cascaded THG...High-efficiency single crystal cascaded third-harmonic generation(THG)was realized inβ-BaB_(2)O_(4)(BBO)material with special cut-angle.By analyzing effective nonlinear optical coefficient(d_(eff))of the cascaded THG process,which was composed by type-II frequency doubling and type-I sum-frequency,the optimum phase matching(PM)direction in BBO crystal was determined to be(θ=32.1°,φ=11°).With an optimized 9-mm long sample which was processed along this direction,the highest cascaded THG conversion efficiency reached 42.3%,which is much superior to the similar components reported previously,including ADP,KDP,and Gd_(x)Y_(1-x)COB crystals.展开更多
The crystallographic properties and R aman spectra of the title compound ZnCd(SCN) 4, which is a new nonlinear optica l crystal(NLO), are reported for the first time. This crystal is orthorhombic and its space group i...The crystallographic properties and R aman spectra of the title compound ZnCd(SCN) 4, which is a new nonlinear optica l crystal(NLO), are reported for the first time. This crystal is orthorhombic and its space group is I - 4 with unit cell parameters a =1.113 5(0.2) nm, c =0.437 60(1) nm. There are two formulas per unit cell. Raman spectra of zinc cadmium thiocyanatec (ZCTC) are given and the electron activities in the crystal are shown.展开更多
As the key components of all-solid-state deep-ultraviolet(DUV,λ<200 nm)laser sources,exploring DUV nonlinear optical(NLO)materials has been a research hotspot for a long time.However,as the only material that has ...As the key components of all-solid-state deep-ultraviolet(DUV,λ<200 nm)laser sources,exploring DUV nonlinear optical(NLO)materials has been a research hotspot for a long time.However,as the only material that has been practically used to generate DUV coherent light through the direct second harmonic generation(SHG)process,KBe_(2)BO_(3)F_(2)(KBBF)still meets bottlenecks,namely,severe layered crystal growth tendency,for extensive application.In the search for the next generation of DUV NLO materials,fluorooxoborates are highly expected due to their excellent NLO performances,flexible structures,and rich structural chemistry.So far,a large number of materials with prominent properties have emerged in the fluorooxoborate system.By investigating the differences in structures and properties among fluorooxoborates and borates and borate fluorides,the excellent NLO per-formances of fluorooxoborates are attributed to functionalized B-O/F chromophores.In this review,by analyzing the published fluorooxoborates,the fluorooxoborate system is a precious treasure for exploring DUV NLO ma-terials.The synthesis,structures,and properties of some representative fluorooxoborates in the research history are introduced and summarized.Finally,we put forward the opportunities and challenges of future research in fluorooxoborate DUV NLO crystals.展开更多
Barium metaborate (BaB 2O 4) exists in two forms the high temperature for m α phase and the low temperature form β phase,with the phase transition poi nt at around 925℃.The low temperature phase (β BBO) is an exce...Barium metaborate (BaB 2O 4) exists in two forms the high temperature for m α phase and the low temperature form β phase,with the phase transition poi nt at around 925℃.The low temperature phase (β BBO) is an excellent NLO cryst al for UV region,while the high temperature one (α BBO) is known as a good bir efringent material.α BBO crystal possesses better transparency in the ultravio let region compared with commonly used YVO 4 and CaCO 3 crystals.However,due t o phase transition problem,it is difficult to grow single α BBO crystals by D CZ method,which restricts its wider application.α BBO crystal usually cracks upon cooling resulted from phase transition to β phase.Therefore,it is difficult to grow β BBO single crystals directly from pure BaB 2O 4 mel t;however,to grow single crystals of α BBO is not easy,either. Our recent experiments showed that one could avoid cracking of α BBO cryst als by Sr 2+ doping.This minute amount of Sr 2+ plays the role of structure stabilizer,which inhibits structural reconstruction. In this way,Sr 2+ d op ed BBO single crystals do not subject to phase transition from 925℃ down to roo m temperature. We have mow successfully grown out α BBO single crystals 30mm in diameter by D CZ method from Sr x Ba 1- x BO 4 melt with Sr concentration 0.3 0 .5%.The ratation rate is 10 15r/min,pulling speed is 1 2mm/h.Preliminary tests revealed that its structure and physic chemical properties were almost identic al to those grown from pure melts.These Sr 2+ doped α BBO crystals are no w being widely used in optical isolators.展开更多
Process of crystal growth can be controlled by both surface kinetics and by volume transport as well.Although the complicated relation between the surface kinetics and volume transport exsits,generally,they are studie...Process of crystal growth can be controlled by both surface kinetics and by volume transport as well.Although the complicated relation between the surface kinetics and volume transport exsits,generally,they are studied seprately.Due to the mathematical complexity of heat and mass transport equations,the in depth studies of heat and mass transport process become difficult.Most of the studies on the transport were performed for the growth from melt.Most of the work on Surface kinetics has been done for crystal growth from aqueous solution because the in situ observation of crystal growth is easily carried out.In recent years,the surface kinetics studies on the nanometer scale,even atomic scale,are demonstrated by using AFM.展开更多
文摘Large crystal NPP-OTs has been obtained by growth from solution,its powder SHG efficiency is 1/3 of urea.It shows it is a new convenient approach to obtain organic second-order NLO crystal:the dipole-dipole interaction is oppos- ed by introducing a large side group.
文摘The structure of ZnL2Cl2 (L=4-methoxybenzaldehyde thiosemicarbazone) has beenobtained by x-ray diffraction. The compound crystallized in space group Cc with Z=4, in a unit cellof dimensions, a=9.08909(10), b=22. l420(10), c=11 .7890(l0)A,β=90.050(10)°, v=2374.6(12)A3,Dc=1 .552gcm-3. H=1 .463mm-1. R=0.0338. and Rw=0.0418. The structure contains individualZnL2Cl2 distorted tetrahedral units in which L molecules are S-bonded as monodentate to the metalions; chloride ions are also coordinated. The nonlinear optical properties of the zinc complex arealso presented in this letter.
基金supported by the National Natural Science Foundation of China(Grant No.21975062)Hebei Province Outstanding Youth Fund(Grant No.E2020201003)+1 种基金Science and Technology Project of Hebei Education Department(Grant Nos.ZD2022156,BJ2020020)Key Projects of Scientific Research and Cultivation Fund of Baoding University(Grant No.2022Z01).
文摘Nonlinear optical(NLO)materials play an increasingly important role in laser technology.Birefringence is one of the most important parameters for NLO materials to realize angle phase-matching conditions.In comparison with other desirable optical properties,the availability of birefringence and refractive index dispersion is especially problematic owing to the strict requirements for single crystals.In this review,we described how to obtain the refractive index and birefringence of NLO materials from crystals sub-millimeters to centimeters in size.Espe-cially,recently developed methods including the minimum deflection angle method,auto-collimation method,prism coupling method,oil immersion technique,interference color method,and theoretical calculation(DFT)for rapid assessment of birefringence are summarized,the contents of which are mainly focused on the principles and typical applications,together with the advantages and drawbacks.In addition,representative examples of bire-fringent measurements were presented.The purpose of this work is to provide a useful perspective on the characterization of birefringence for NLO materials.It is hoped that this review can give a clear description of the birefringence measurements and accelerate the discovery of new NLO crystals.
文摘A novel tolane 4-methoxy-4'-nitro-diphenyl-acetylene (MONA) has been prepared quantitatively by reacting cuprous p-methoxy phenyl-acetylene with p-iodonitrobenzene. A single crystal of the Moan was grown by solution growth method. The crystal was then characterized by X-ray diffraction structure analysis and second-harmonic generation(SHG)investigation. Polymorphous crystal forms of the MONA were grown from different solvents having different nonlinear optical properties depending on their different crystal structures. The relationship between the crystal growth and crystal structure is discusse.
基金supported by the National Natural Science Foundation of China(NSFC 51872297,51890864,11574024)NSAF(U1930402)+1 种基金support from outstanding member in Youth Innovation Promotion Association at the Chinese Academy of Sciences(CAS)Fujian Institute of Innovation(FJCXY18010201)in CAS。
文摘Deep-ultraviolet(DUV)nonlinear optical(NLO)crystal is indispensable in current DUV all-solid-state laser technology,which is the key device to generate DUV light by frequency conversion.Due to stringent criteria,DUV NLO crystals are scarce and their discovery faces a big challenge.Although KBe2BO3F2(KBBF)is already excellent for current uses,the development of DUV science requires the materials with shorter output wavelengths and larger NLO effects,so as to meet the needs of DUV lasers with higher precision and higher power.Therefore,how to efficiently design DUV NLO materials has always been the core issue in NLO materials science.Looking back on the development of NLO materials,it turns out that theoretical modeling and simulation is an effective and efficient method,not only for mechanism understandings,but also for experimental exploration.In this article,in order to accelerate the process of DUV materials discovery,we summarize and propose a powerful computeraided modeling system and design blueprint that can be used to evaluate the DUV NLO performance in a faster way than pure experiments.With this in hand,we enrich the understanding of NLO structure-property correlation,and systematically prospect the DUV NLO properties on the basis of many existing and designed structures according to different structural types and chemical compositions.Seven novel structures are predicted for the first time to exhibit potential DUV NLO capabilities.All the results enable us to believe that the computer-aided modeling blueprint will play an important role in the exploration of new DUV NLO crystals.
文摘zinc cadmium thiocyanate (ZCTC), ZnCd(SCN)_4, has been discoveredas a UV second-order nonlinear optical coordination crystal. Titsthermal and transmission Properties are reported. The thermaldecomposition is characterized by using the X-ray Powder diffraction(XRPD) and infrared (IR) spectroscopy at room temperature. TheAbsorptions of intrinsic ions and ZCTC in a solution state arediscussed as well as Transmission properties of the ZCTC crystal. Aneffective method of reducing the surface Reflection loss of ZCTCcrystal is introduced.
基金Supported by the National Natural Science Foundation of China(Nos.21975255,51890862,21921001 and U1605245)the National Key Research and Development Plan of Ministry of Science and Technology(No.2016YFB0402104)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB20000000)。
文摘UV nonlinear optical(NLO)crystals are essential materials for UV solid state laser output.To date,frequency conversion in UV region is mainly dependent on borates with planar BO3 or B3O6 units.Since the practical applications require more and more high comprehensive properties of crystals,it is urgent to develop new UV NLO crystals.However,it is more and more difficult to find new borate NLO crystals because borate NLO crystals have been studied for several decades.Therefore,it is important to search new systems for the exploration of UV NLO crystals.Based on the relationship between the microstructure and properties of the groups,we proposed that inorganic(CO3)2-and(NO3)-groups can be as new NLO active units for UV NLO crystals because they haveπ-conjugated configuration.Accordingly,our group have performed related work in carbonate and nitrate systems in recent years,which resulted in finding some excellent carbonates and nitrates NLO crystals.In addition,we have recently expanded the research field from inorganic to organicπ-conjugated systems,such as isocyanurates.This mini review will introduce the research results of our team in the field of UV NLO crystals including carbonates,nitrates and cyanurates in recent years.
文摘The phase-matching for nonlinear optical crystal, the nonlinear phase matching angle, effective nonlinear coefficient, walk-off angles, permitted angle, and permitted wavelength are obtained in type-I and type-II phase matching in ultraviolet （UV） nonlinear optical crystals CsLiB6O10 （CLBO） and K2Al2B2O7 （KABO） by detailed theoretical simulation. Through analysis and comparison, the phase matching characteristics of the second harmonic generation in the crystals are discussed when the wavelengths of the basic frequency lights turn continually.
基金This work was supported by the National Basic Research Project of China(No.2010CB630701)the National Natural Science Foundation of China(No.91022036).
文摘Nonlinear optical(NLO)crystals have been playing an increasingly important role in laser science and technology.The NLO crystals used in the middle infrared(mid-IR)region,compared with the NLO crystals in the other wavelength regions,are still not good enough for the application of high-energy laser.The main defect is that their laser damage thresholds(LDT)are low.Chinese scientists have made a lot of important contributions to the UV and visible NLO crystals.In the last decade,they also did a lot of work on the mid-IR NLO materials.The main purpose of these researches is to increase the LDT and simultaneously balance the other properties.This paper presents a brief summary of their research progress in this topic on three types of materials:chalcogenides,oxides,and halides.The emphasis is put on the design strategy and quality control of the crystals.
文摘Benzoyl glycine （BG） is a promising organic nonlinear optical （NLO） crystal, whose second harmonic generation （SHG） efficiency is much higher than that of KDP （potassium dihydrogen phosphate）. Single crystals of pure, Cu2＋ and Cd2＋ doped BG were grown by slow evaporation technique. Optically transparent and defect free single crystals of size up to 10 mm×15 mm×10 mm were harvested in a period of 40-60 days. The growth conditions of pure and doped crystals of BG were optimized and the grown crystals were confirmed by single crystal XRD （X-ray diffraction）. The grown crystals were characterized by FTIR （Fourier transform infrared spectroscopy）, optical absorption and microhardness studies. The microhardness studies confirm that BG has a moderate VHN （Vickers hardness number） value in comparison to the.other organic NLO crystals. The efficiency of frequency doubling was measured for the using Nd：YAG laser and the results were discussed.
文摘We report high-energy tunable 6.5-12 μm ps mid-infrared radiation generation based on OPA pumped using 1064 nm laser in LISe crystal.We simulated the relationship between the idler energy and crystal length.An optimum LISe length of 4 mm was used to enhance the idler energy experimentally.At a pump energy of ~9.4 mJ, energy levels of ~146 and of ~27 μJ are generated at 6.5 μm and 12 μm, respectively.The highest energy of ~205 μJ is achieved at 8.1 μm at a pump energy of ~19 mJ.Finally, the angular and spectral width acceptance are measured.
基金supported by the National Natural Science Foundation of China(grant nos.22222510,21975255,21921001)the Foundation of Fujian Science&Technology Innovation Laboratory(grant no.2021ZR202)the Youth Innovation Promotion Association CAS(grant no.2019303).
文摘In this study,the first methyl sulfonate deepultraviolet(DUV)nonlinear optical(NLO)crystal,Ba(SO_(3)CH_(3))_(2),was successfully synthesized with the polar non-π-conjugated tetrahedron,SO_(3)CH_(3)^(−),as a novel DUV NLO building unit.Results showed that Ba(SO_(3)CH_(3))_(2)not only had a very short absorption edge of 159 nm,which is the shortest among reported phase-matchable sulfates or sulfonates,but also exhibited excellent optical properties.(Powder X-ray diffractionwas ca.1.5×KH_(2)PO_(4)and birefringence was 0.04 at 589.3 nm.)It also exhibited high thermal stability and remarkable stability against air and moisture.Additionally,bulk Ba(SO_(3)CH_(3))_(2)crystal could be obtained conveniently from a simple solution evaporation process.Therefore,Ba(SO_(3)CH_(3))_(2)should have great potential as a DUV NLO crystal in the near future.
文摘Functional crystals are the basic materials for the development of modern science and technology and are playing key roles in the modern information era. In this paper, we review functional crystals in China, including research history, significant achievements, and important applications by highlighting the most recent progress in research. Challenges for the development of functional materials are discussed and possible directions for development are proposed by focusing on potential strengths of these materials.
基金supported by the National Key Basic Research Program of China(Grant No.2013CB922402)the Key Program of the National Natural Science Foundation of China(Grant Nos.11434016 and 61575219)the International Joint Research Program of the National Natural Science Foundation of China(Grant No.61210017)
文摘The third harmonic generation（THG） of a linear cavity Ti：sapphire regenerative amplifier by use of a K3B6O（10）Cl（KBOC） crystal is studied for the first time. Output power up to 5.9 mW is obtained at a central wavelength of 263 nm,corresponding to a conversion efficiency of 4.5% to the second harmonic power. Our results show a tremendous potential for nonlinear frequency conversion into the deep ultraviolet range with the new crystal and the output laser power can be further improved.
基金Project supported by the National Key Basic Research Program of China(Grant Nos.2013CB922401 and 2013CB922402)the National Natural Science Foundation of China(Grant Nos.11474002,61205130,and 61575219)
文摘K3B6O10Cl （KBOC）, a new nonlinear optical crystal, shows potential advantages for the generation of deep ultraviolet （UV） light compared with other borate crystals. In this paper we study for the first time the second harmonic generation （SHG） of a femtosecond Ti：sapphire amplifier with this crystal. Laser power is obtained to be as high as 220 mW at the central wavelength of 396 nm with a 1-mm-long crystal, and the maximum SHG conversion efficiency reaches 39.3%. The typical pulse duration is 83 fs, The results show that second harmonic （SH） conversion efficiency has the room to be further improved and that the new nonlinear crystal is very suited to generate the high efficiency deep ultraviolet laser radiation below 266 nm.
基金Project supported by the Natural Science Foundation of Shandong Province,China(Grant Nos.ZR2017MF031 and ZR2018BF029)
文摘High-efficiency single crystal cascaded third-harmonic generation(THG)was realized inβ-BaB_(2)O_(4)(BBO)material with special cut-angle.By analyzing effective nonlinear optical coefficient(d_(eff))of the cascaded THG process,which was composed by type-II frequency doubling and type-I sum-frequency,the optimum phase matching(PM)direction in BBO crystal was determined to be(θ=32.1°,φ=11°).With an optimized 9-mm long sample which was processed along this direction,the highest cascaded THG conversion efficiency reached 42.3%,which is much superior to the similar components reported previously,including ADP,KDP,and Gd_(x)Y_(1-x)COB crystals.
文摘The crystallographic properties and R aman spectra of the title compound ZnCd(SCN) 4, which is a new nonlinear optica l crystal(NLO), are reported for the first time. This crystal is orthorhombic and its space group is I - 4 with unit cell parameters a =1.113 5(0.2) nm, c =0.437 60(1) nm. There are two formulas per unit cell. Raman spectra of zinc cadmium thiocyanatec (ZCTC) are given and the electron activities in the crystal are shown.
基金supported by the National Natural Science Foundation of China(22275208,22122509)the Youth Innovation Promotion Association CAS(2020429)+2 种基金the National Key R&D Program of China(2021YFB3601501)the Xinjiang Major Science and Technology Project(2021A01001-3)CAS Project for Young Scientists in Basic Research(YSBR-024).
文摘As the key components of all-solid-state deep-ultraviolet(DUV,λ<200 nm)laser sources,exploring DUV nonlinear optical(NLO)materials has been a research hotspot for a long time.However,as the only material that has been practically used to generate DUV coherent light through the direct second harmonic generation(SHG)process,KBe_(2)BO_(3)F_(2)(KBBF)still meets bottlenecks,namely,severe layered crystal growth tendency,for extensive application.In the search for the next generation of DUV NLO materials,fluorooxoborates are highly expected due to their excellent NLO performances,flexible structures,and rich structural chemistry.So far,a large number of materials with prominent properties have emerged in the fluorooxoborate system.By investigating the differences in structures and properties among fluorooxoborates and borates and borate fluorides,the excellent NLO per-formances of fluorooxoborates are attributed to functionalized B-O/F chromophores.In this review,by analyzing the published fluorooxoborates,the fluorooxoborate system is a precious treasure for exploring DUV NLO ma-terials.The synthesis,structures,and properties of some representative fluorooxoborates in the research history are introduced and summarized.Finally,we put forward the opportunities and challenges of future research in fluorooxoborate DUV NLO crystals.
文摘Barium metaborate (BaB 2O 4) exists in two forms the high temperature for m α phase and the low temperature form β phase,with the phase transition poi nt at around 925℃.The low temperature phase (β BBO) is an excellent NLO cryst al for UV region,while the high temperature one (α BBO) is known as a good bir efringent material.α BBO crystal possesses better transparency in the ultravio let region compared with commonly used YVO 4 and CaCO 3 crystals.However,due t o phase transition problem,it is difficult to grow single α BBO crystals by D CZ method,which restricts its wider application.α BBO crystal usually cracks upon cooling resulted from phase transition to β phase.Therefore,it is difficult to grow β BBO single crystals directly from pure BaB 2O 4 mel t;however,to grow single crystals of α BBO is not easy,either. Our recent experiments showed that one could avoid cracking of α BBO cryst als by Sr 2+ doping.This minute amount of Sr 2+ plays the role of structure stabilizer,which inhibits structural reconstruction. In this way,Sr 2+ d op ed BBO single crystals do not subject to phase transition from 925℃ down to roo m temperature. We have mow successfully grown out α BBO single crystals 30mm in diameter by D CZ method from Sr x Ba 1- x BO 4 melt with Sr concentration 0.3 0 .5%.The ratation rate is 10 15r/min,pulling speed is 1 2mm/h.Preliminary tests revealed that its structure and physic chemical properties were almost identic al to those grown from pure melts.These Sr 2+ doped α BBO crystals are no w being widely used in optical isolators.
文摘Process of crystal growth can be controlled by both surface kinetics and by volume transport as well.Although the complicated relation between the surface kinetics and volume transport exsits,generally,they are studied seprately.Due to the mathematical complexity of heat and mass transport equations,the in depth studies of heat and mass transport process become difficult.Most of the studies on the transport were performed for the growth from melt.Most of the work on Surface kinetics has been done for crystal growth from aqueous solution because the in situ observation of crystal growth is easily carried out.In recent years,the surface kinetics studies on the nanometer scale,even atomic scale,are demonstrated by using AFM.
