Although the current workhorse in the area of second-order nonlinear optical (NLO) materials is still the inorganic NLO crystals, organic NLO crystals have their own bright aspects such as the high molecular NLO coefficient and structural diversity and flexibility. In principle, there is no distinct boundary between inorganic and organic. People hoped to develop a new kind of semi-organic NLO crystals which combine the advantages of inorganic and organic materials together.
{"title":"Recent Progress of Semi-organic Nonlinear Optical Crystals","authors":"M. Jiang, Q. Fang, D. Yuan, D. Xu, Ming Liu","doi":"10.1364/sslma.1997.wb3","DOIUrl":"https://doi.org/10.1364/sslma.1997.wb3","url":null,"abstract":"Although the current workhorse in the area of second-order nonlinear optical (NLO) materials is still the inorganic NLO crystals, organic NLO crystals have their own bright aspects such as the high molecular NLO coefficient and structural diversity and flexibility. In principle, there is no distinct boundary between inorganic and organic. People hoped to develop a new kind of semi-organic NLO crystals which combine the advantages of inorganic and organic materials together.","PeriodicalId":348889,"journal":{"name":"Solid State Lasers: Materials and Applications","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121175783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pico- and femto-second pulses are becoming powerful tools in chemistry, biology, medicine, and industry. High price for auto-correlators, nonlinear crystals and their low quantum efficiency of Second Harmonic Generation in Near Infrared region have encouraged the search of alternative approaches. It has been demonstrated recently that Si and GaAsP photodiodes and CdS photoconductive cell [1] and even unbiased Light Emitting Diodes (LED) [2] can replace nonlinear crystals and photodetectors in autocorrelators for characterisation of powerful ultrashort laser pulses. Specially fabricated waveguide structures have provided much higher sensitivity due to longer length of interaction [3,4]. However, waveguide configuration suffers from low coupling efficiency into waveguide and reduction of temporal resolution due to dispersion.
{"title":"High sensitivity autocorrelation using Light Emitting Diode","authors":"G. Voevodkin","doi":"10.1364/sslma.1997.thd4","DOIUrl":"https://doi.org/10.1364/sslma.1997.thd4","url":null,"abstract":"Pico- and femto-second pulses are becoming powerful tools in chemistry, biology, medicine, and industry. High price for auto-correlators, nonlinear crystals and their low quantum efficiency of Second Harmonic Generation in Near Infrared region have encouraged the search of alternative approaches. It has been demonstrated recently that Si and GaAsP photodiodes and CdS photoconductive cell [1] and even unbiased Light Emitting Diodes (LED) [2] can replace nonlinear crystals and photodetectors in autocorrelators for characterisation of powerful ultrashort laser pulses. Specially fabricated waveguide structures have provided much higher sensitivity due to longer length of interaction [3,4]. However, waveguide configuration suffers from low coupling efficiency into waveguide and reduction of temporal resolution due to dispersion.","PeriodicalId":348889,"journal":{"name":"Solid State Lasers: Materials and Applications","volume":"271 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115300777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The advantages of using fiber beam delivery for high-power Nd:YAG lasers were well known. In many cases, high-power YAG laser was one kind of multimode laser, its beam quality was evaluated by beam parameter product ω θ . At a given output power, the laser beam parameter product was a constant, which is only related to laser resonator structure.
{"title":"High-Power Nd:YAG Laser Beam Delivery by Optical Fiber","authors":"X.L. Wang, R. Zhang, J. Yao","doi":"10.1364/sslma.1997.fb6","DOIUrl":"https://doi.org/10.1364/sslma.1997.fb6","url":null,"abstract":"The advantages of using fiber beam delivery for high-power Nd:YAG lasers were well known. In many cases, high-power YAG laser was one kind of multimode laser, its beam quality was evaluated by beam parameter product ω θ . At a given output power, the laser beam parameter product was a constant, which is only related to laser resonator structure.","PeriodicalId":348889,"journal":{"name":"Solid State Lasers: Materials and Applications","volume":"333 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114964305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Past of Nonlinear Optical Frequency Conversion Technology • Material: KTP, ADP, LiNbO3(MgO:LiNbO3), LiIO3, BNN. • Technology: SHG, THG, OPO. • Application: – SHG ( and THG) of Nd:YAG Laser – Visible and near-infrared.
{"title":"Laser Frequency Conversion Technology and Application","authors":"Jian-quan Yao","doi":"10.1364/sslma.1997.tud1","DOIUrl":"https://doi.org/10.1364/sslma.1997.tud1","url":null,"abstract":"I. Past of Nonlinear Optical Frequency Conversion Technology\u0000 • Material: KTP, ADP, LiNbO3(MgO:LiNbO3), LiIO3, BNN.\u0000 • Technology: SHG, THG, OPO.\u0000 • Application:\u0000 – SHG ( and THG) of Nd:YAG Laser\u0000 – Visible and near-infrared.","PeriodicalId":348889,"journal":{"name":"Solid State Lasers: Materials and Applications","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128049337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Otomo, G. Stegeman, M. C. Flipse, M. Diemeer, W. Horsthuis, G. R. Möhlmann
Until recently, second harmonic generation (SHG) was used to extend the wavelength capability of high power lasers. In the conventional SHG process the fundamental and the growing second harmonic propagate together (Fig. 1a). The most recent progress has allowed mW of doubled power to be generated with 100’s of mW of input fundamental power. This has been achieved with waveguides from dielectric media such as LiNbO3, KTiOPO4 (KTP), etc.1,2 Organic materials have attracted attention due to their possible large nonlinearity. Although there has been some excellent pioneering work using organic materials, organic waveguide doublers have not yet achieved such efficiencies.3,4 One of the problems has been the disadvantageous trade-offs between λmax, the magnitude of the nonlinearity and the absorption of the doubled light. A different SHG interaction geometry, in which the second harmonic radiates upwards from a waveguide surface by mixing the counter-propagating fundamental guided waves (Fig. 1b), was reported 16 years ago, primarily for using second order interactions for signal manipulation and processing.5,6 The early works concentrated on ion-exchanged LiNbO3 waveguides with quite small conversion efficiencies. More recently AlGaAs multi layer waveguides have been used as a form of quasi-phase matching (QPM) in the transverse direction with much larger nonlinear cross-section coefficients. A number of interesting applications have been demonstrated including convolution, a spectrometer, etc. This interaction has different trade-offs from the usual copropagating case. The signal at the harmonic frequency only traverses the waveguide depth so that the attenuation coefficient can be as large as 104 cm-1 and hence the interaction length is limited primarily by attenuation at the fundamental wavelength. As a result the harmonic wavelength can in principle be near λmax, the peak absorption wavelength, and hence utilize a resonantly enhanced nonlinearity. The fractional power conversion into SHG for the co-propagating and the counter-propagating schemes is proportional to [deff(2)L]2I and [deff(2)L]2LHI respectively. I is the intensity and deff(2) , L and H are the effective second order nonlinearity, the effective interaction length and the waveguide depth respectively. In terms of efficient SHG, the key question is whether the resonant enhancement in [deff(2)]2 is larger or comparable to L/H. This represents the trade-off between co-propagating and counter-propagating SHG. If indeed the trade-offs are comparable, this counter-propagating approach could be attractive because there are no wavevector matching constraints as there are in co-propagating SHG. Such constraints have made it difficult to obtain phase-matching over a centimeter, require precise wavelength tuning and control of the input laser, and tight temperature control of the waveguide. Thus the large nonlinearity of poled polymers can be effectively utilized for SHG in the counter-propa
{"title":"Counter-propagating mixing second harmonic generation in poled polymer waveguides","authors":"A. Otomo, G. Stegeman, M. C. Flipse, M. Diemeer, W. Horsthuis, G. R. Möhlmann","doi":"10.1364/sslma.1997.tha3","DOIUrl":"https://doi.org/10.1364/sslma.1997.tha3","url":null,"abstract":"Until recently, second harmonic generation (SHG) was used to extend the wavelength capability of high power lasers. In the conventional SHG process the fundamental and the growing second harmonic propagate together (Fig. 1a). The most recent progress has allowed mW of doubled power to be generated with 100’s of mW of input fundamental power. This has been achieved with waveguides from dielectric media such as LiNbO3, KTiOPO4 (KTP), etc.1,2 Organic materials have attracted attention due to their possible large nonlinearity. Although there has been some excellent pioneering work using organic materials, organic waveguide doublers have not yet achieved such efficiencies.3,4 One of the problems has been the disadvantageous trade-offs between λmax, the magnitude of the nonlinearity and the absorption of the doubled light. A different SHG interaction geometry, in which the second harmonic radiates upwards from a waveguide surface by mixing the counter-propagating fundamental guided waves (Fig. 1b), was reported 16 years ago, primarily for using second order interactions for signal manipulation and processing.5,6 The early works concentrated on ion-exchanged LiNbO3 waveguides with quite small conversion efficiencies. More recently AlGaAs multi layer waveguides have been used as a form of quasi-phase matching (QPM) in the transverse direction with much larger nonlinear cross-section coefficients. A number of interesting applications have been demonstrated including convolution, a spectrometer, etc. This interaction has different trade-offs from the usual copropagating case. The signal at the harmonic frequency only traverses the waveguide depth so that the attenuation coefficient can be as large as 104 cm-1 and hence the interaction length is limited primarily by attenuation at the fundamental wavelength. As a result the harmonic wavelength can in principle be near λmax, the peak absorption wavelength, and hence utilize a resonantly enhanced nonlinearity. The fractional power conversion into SHG for the co-propagating and the counter-propagating schemes is proportional to \u0000[deff(2)L]2I and \u0000[deff(2)L]2LHI respectively. I is the intensity and \u0000deff(2) , L and H are the effective second order nonlinearity, the effective interaction length and the waveguide depth respectively. In terms of efficient SHG, the key question is whether the resonant enhancement in \u0000[deff(2)]2 is larger or comparable to L/H. This represents the trade-off between co-propagating and counter-propagating SHG. If indeed the trade-offs are comparable, this counter-propagating approach could be attractive because there are no wavevector matching constraints as there are in co-propagating SHG. Such constraints have made it difficult to obtain phase-matching over a centimeter, require precise wavelength tuning and control of the input laser, and tight temperature control of the waveguide. Thus the large nonlinearity of poled polymers can be effectively utilized for SHG in the counter-propa","PeriodicalId":348889,"journal":{"name":"Solid State Lasers: Materials and Applications","volume":"2014 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128060693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The first laser of China was built at Changchun Institute of Optics and Fine Mechanics, Academia Sinica, in September 1961. It was ruby laser also ,but the design was a little different from the laser invented by T.H.Maiman in May 1960. It applied spherical mirror instead of cylindrical one and straight tube flash lamp instead of spiral one.
{"title":"Solid-state Laser and Its Applications in China","authors":"Mei Sui-sheng","doi":"10.1364/sslma.1997.tuc1","DOIUrl":"https://doi.org/10.1364/sslma.1997.tuc1","url":null,"abstract":"The first laser of China was built at Changchun Institute of Optics and Fine Mechanics, Academia Sinica, in September 1961. It was ruby laser also ,but the design was a little different from the laser invented by T.H.Maiman in May 1960. It applied spherical mirror instead of cylindrical one and straight tube flash lamp instead of spiral one.","PeriodicalId":348889,"journal":{"name":"Solid State Lasers: Materials and Applications","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127039783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shen Yuquan, Ling Qiu, Zhang Jiaxing, Zhai Jianfeng, Si Jinhai, Wang Yougui, Z. Jiang, Zou Bingsuo, Ye Peixian, Zou Yinghua, Xia Zonggiu, Y. Ping
Optical Kerr effect(OKE) and optical bistability(OB) are the important basis for optical switching. Nitrobenzene is an organic OKE material, however, it is not convenient to handle because of its liquid form and its toxicity. Other inorganic crystals such as tantalum potassium niobate and barium titanate are good candidates to replace nitrobenzene, but they have the problem of high price. On the other hand, optical bistability with low input power and slow temporal response in organic polymer waveguide was observed by us recently from push-pull aromatic azobenzene materials1 and optical bistabilities realized in a planar quasi waveguide and a hybrid waveguide made with a polydiacetylene film have also been reported in literature2. Meanwhile, much efforts have continuously been devoted to the search for such better organic materials in thin film form: metallo phthalocyanine is one among them. However, to our knowledge, study of ultrafast optical bistability in organic polymer waveguides has not yet been reported before us. In this paper, we are going to report our recent progresses on the study of the ultrafast optical switch properties of a novel vanadium phthalocyanine, the picosecond response OKE and OB observed from its Langmuir-Blodegett film or from a planar optical waveguide. In addition, the relationship between the chemical structure and the property of ultrafast responses will also be discussed.
{"title":"Recent Progresses on the Study of Ultrafast Optical Switching: Materials and Devices","authors":"Shen Yuquan, Ling Qiu, Zhang Jiaxing, Zhai Jianfeng, Si Jinhai, Wang Yougui, Z. Jiang, Zou Bingsuo, Ye Peixian, Zou Yinghua, Xia Zonggiu, Y. Ping","doi":"10.1364/sslma.1997.thd3","DOIUrl":"https://doi.org/10.1364/sslma.1997.thd3","url":null,"abstract":"Optical Kerr effect(OKE) and optical bistability(OB) are the important basis for optical switching. Nitrobenzene is an organic OKE material, however, it is not convenient to handle because of its liquid form and its toxicity. Other inorganic crystals such as tantalum potassium niobate and barium titanate are good candidates to replace nitrobenzene, but they have the problem of high price. On the other hand, optical bistability with low input power and slow temporal response in organic polymer waveguide was observed by us recently from push-pull aromatic azobenzene materials1 and optical bistabilities realized in a planar quasi waveguide and a hybrid waveguide made with a polydiacetylene film have also been reported in literature2. Meanwhile, much efforts have continuously been devoted to the search for such better organic materials in thin film form: metallo phthalocyanine is one among them. However, to our knowledge, study of ultrafast optical bistability in organic polymer waveguides has not yet been reported before us. In this paper, we are going to report our recent progresses on the study of the ultrafast optical switch properties of a novel vanadium phthalocyanine, the picosecond response OKE and OB observed from its Langmuir-Blodegett film or from a planar optical waveguide. In addition, the relationship between the chemical structure and the property of ultrafast responses will also be discussed.","PeriodicalId":348889,"journal":{"name":"Solid State Lasers: Materials and Applications","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127210276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fibre lasers have been one of the most active areas of laser development over the past decade. The fibre geometry provides high gain for a modest pump power and this has been the feature most widely exploited. The later advent of fibre gratings has further enhanced the versatility of active fibre devices. Now, there is increasing interest in the high power capabilities of fibre lasers, via cladding-pumped configurations, so that fibre lasers provide competitive solutions to areas formerly regarded as the sole province of bulk lasers. These aspects and other important developments that have taken place over the last decade will be reviewed.
{"title":"Fibre Optical Lasers","authors":"D. Hanna","doi":"10.1364/sslma.1997.fb1","DOIUrl":"https://doi.org/10.1364/sslma.1997.fb1","url":null,"abstract":"Fibre lasers have been one of the most active areas of laser development over the past decade. The fibre geometry provides high gain for a modest pump power and this has been the feature most widely exploited. The later advent of fibre gratings has further enhanced the versatility of active fibre devices. Now, there is increasing interest in the high power capabilities of fibre lasers, via cladding-pumped configurations, so that fibre lasers provide competitive solutions to areas formerly regarded as the sole province of bulk lasers. These aspects and other important developments that have taken place over the last decade will be reviewed.","PeriodicalId":348889,"journal":{"name":"Solid State Lasers: Materials and Applications","volume":"147 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114117699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Many deffercnt diode-pumped single-frequency solid-atate lasers have been demonstrated in recent years. The LD pumped tunable single frequency polarized laser is of greet importance for precision measurements. A LD pumped 1.06μm single frequency Nd:YAG micro-chip laser with 120GHz of tunable frequency range and 0.5 mW of output power has been reported. For some important applications the higher laser power and polarized laser beam are needed. We have reported the LD pumped CW and pulsed micro-chip Nd:YVO4 laser with high polarized output power. Here we report the LD pumped tunable single frequency Nd:YVO4 laser with higher output power and polarized beam.
{"title":"LD Pumped Tunable Single Frequency Polarized Nd:YVO4 Laser","authors":"Yujing Huo, Shufang He","doi":"10.1364/sslma.1997.fa6","DOIUrl":"https://doi.org/10.1364/sslma.1997.fa6","url":null,"abstract":"Many deffercnt diode-pumped single-frequency solid-atate lasers have been demonstrated in recent years. The LD pumped tunable single frequency polarized laser is of greet importance for precision measurements. A LD pumped 1.06μm single frequency Nd:YAG micro-chip laser with 120GHz of tunable frequency range and 0.5 mW of output power has been reported. For some important applications the higher laser power and polarized laser beam are needed. We have reported the LD pumped CW and pulsed micro-chip Nd:YVO4 laser with high polarized output power. Here we report the LD pumped tunable single frequency Nd:YVO4 laser with higher output power and polarized beam.","PeriodicalId":348889,"journal":{"name":"Solid State Lasers: Materials and Applications","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114885145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Electro-optic (E-O) polymers have drawn great interests in recent years because of their potential applications in photonics devices such as electro-optic modulators and switches, optical data storage and information processing1-2. Recent interests have been focused on the design and development of polymeric material systems (active and passive) with large E-O coefficients and high thermal, temporal, chemical and phtochemical stability3-8. The E-O response of a active polymer commonly arises from the electric field induced alignment of its second-order nonlinear optical (NLO) chromophore, either doped as a guest/host system or covalently bonded as a side-chain. Because of the strong interaction among the electric dipoles, the poled structure is in a meta-stable state; the poled NLO chromophores which possess large dipole moment will tend to relax back to the randomly oriented state. As a result, the stability of the poled structure strongly depends on the rigidity of the overall material system. This paper provides a brief review of the latest developments of highly efficient and thermally stable chromophores and polymers for device applications.
{"title":"Recent Progress of Electro-optic Polymers for Device Applications","authors":"A. Jen, Qing Yang, S. Marder, L. Dalton, C. Shu","doi":"10.1557/PROC-488-193","DOIUrl":"https://doi.org/10.1557/PROC-488-193","url":null,"abstract":"Electro-optic (E-O) polymers have drawn great interests in recent years because of their potential applications in photonics devices such as electro-optic modulators and switches, optical data storage and information processing1-2. Recent interests have been focused on the design and development of polymeric material systems (active and passive) with large E-O coefficients and high thermal, temporal, chemical and phtochemical stability3-8. The E-O response of a active polymer commonly arises from the electric field induced alignment of its second-order nonlinear optical (NLO) chromophore, either doped as a guest/host system or covalently bonded as a side-chain. Because of the strong interaction among the electric dipoles, the poled structure is in a meta-stable state; the poled NLO chromophores which possess large dipole moment will tend to relax back to the randomly oriented state. As a result, the stability of the poled structure strongly depends on the rigidity of the overall material system. This paper provides a brief review of the latest developments of highly efficient and thermally stable chromophores and polymers for device applications.","PeriodicalId":348889,"journal":{"name":"Solid State Lasers: Materials and Applications","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125401333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：