Pub Date : 1996-11-18DOI: 10.1109/LEOS.1996.571610
J. Park, H. Taylor
Summary form only given. An internal mirror in a continuous length of optical fiber has been a basic component for a variety of devices in optical fiber communication systems. Hence, some kinds of internal mirrors have been fabricated, but none of them was low reflectance internal mirror with low insertion loss. Low reflectance mirrors with low insertion loss were produced using mechanical splices and pieces of fiber coated with a TiO/sub 2/ film. These mirrors can be used as partial reflectors in the optical fiber transversal filters. The fabrication procedures of internal mirrors is presented.
{"title":"Low reflectance internal mirrors","authors":"J. Park, H. Taylor","doi":"10.1109/LEOS.1996.571610","DOIUrl":"https://doi.org/10.1109/LEOS.1996.571610","url":null,"abstract":"Summary form only given. An internal mirror in a continuous length of optical fiber has been a basic component for a variety of devices in optical fiber communication systems. Hence, some kinds of internal mirrors have been fabricated, but none of them was low reflectance internal mirror with low insertion loss. Low reflectance mirrors with low insertion loss were produced using mechanical splices and pieces of fiber coated with a TiO/sub 2/ film. These mirrors can be used as partial reflectors in the optical fiber transversal filters. The fabrication procedures of internal mirrors is presented.","PeriodicalId":332726,"journal":{"name":"Conference Proceedings LEOS'96 9th Annual Meeting IEEE Lasers and Electro-Optics Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115439295","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}
Pub Date : 1996-11-18DOI: 10.1109/LEOS.1996.565114
G. Erber, F. Bugge, J. Sebastian, K. Vogel, H. Wenzel, M. Weyers
High power laser diodes emitting at 800 nm using strained GaAsP- and unstrained InGaAsP-SQWs in the active region are investigated. A very small far field angle of 23/spl deg/ and a high efficiency of 1.1 W/A for 1000 /spl mu/m long laser diodes are achieved. A 1 cm bar with 37.5 % active area shows a CW-output power of 60 W.
{"title":"A study of structures with Al-free QWs in AlGaAs waveguides for laser diodes emitting at 800 nm","authors":"G. Erber, F. Bugge, J. Sebastian, K. Vogel, H. Wenzel, M. Weyers","doi":"10.1109/LEOS.1996.565114","DOIUrl":"https://doi.org/10.1109/LEOS.1996.565114","url":null,"abstract":"High power laser diodes emitting at 800 nm using strained GaAsP- and unstrained InGaAsP-SQWs in the active region are investigated. A very small far field angle of 23/spl deg/ and a high efficiency of 1.1 W/A for 1000 /spl mu/m long laser diodes are achieved. A 1 cm bar with 37.5 % active area shows a CW-output power of 60 W.","PeriodicalId":332726,"journal":{"name":"Conference Proceedings LEOS'96 9th Annual Meeting IEEE Lasers and Electro-Optics Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115565676","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}
Pub Date : 1996-11-18DOI: 10.1109/LEOS.1996.571655
T. Kurokawa
Though TDM (and recently WDM) are generally adopted to increase the total throughput in optical communication systems, SDM must be more effective in most optical interconnection systems. This is because SDM has more advantage in cost and power consumption than TDM, when the transmission distance is rather short, i.e. less than a few hundred meters. VCSEL and smart pixel arrays are very important for constructing optical interconnection systems because they can emit, switch and process a number of broadband optical signals simultaneously. This paper reviews VCSELs and VCSEL-based smart pixels, and discusses the issues for their application to optical interconnections. VCSELs and smart pixels are applicable to three types of parallel optical interconnections: 1) parallel optical fiber link-the optical signals from the SEL array are transmitted through a fiber ribbon for distances less than a few hundred meters; 2) free-space optical interconnects-high-density optical signals from a two-dimensional SEL array are distributed into several ports for distance shorter than one meter; 3) reconfigurable optical interconnects nterconnect patterns among processors are changed dynamically by means of free-space photonic switching networks.
{"title":"Vertical-cavity surface-emitting lasers and smart pixels for optical interconnection systems","authors":"T. Kurokawa","doi":"10.1109/LEOS.1996.571655","DOIUrl":"https://doi.org/10.1109/LEOS.1996.571655","url":null,"abstract":"Though TDM (and recently WDM) are generally adopted to increase the total throughput in optical communication systems, SDM must be more effective in most optical interconnection systems. This is because SDM has more advantage in cost and power consumption than TDM, when the transmission distance is rather short, i.e. less than a few hundred meters. VCSEL and smart pixel arrays are very important for constructing optical interconnection systems because they can emit, switch and process a number of broadband optical signals simultaneously. This paper reviews VCSELs and VCSEL-based smart pixels, and discusses the issues for their application to optical interconnections. VCSELs and smart pixels are applicable to three types of parallel optical interconnections: 1) parallel optical fiber link-the optical signals from the SEL array are transmitted through a fiber ribbon for distances less than a few hundred meters; 2) free-space optical interconnects-high-density optical signals from a two-dimensional SEL array are distributed into several ports for distance shorter than one meter; 3) reconfigurable optical interconnects nterconnect patterns among processors are changed dynamically by means of free-space photonic switching networks.","PeriodicalId":332726,"journal":{"name":"Conference Proceedings LEOS'96 9th Annual Meeting IEEE Lasers and Electro-Optics Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115352240","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}
Pub Date : 1996-11-18DOI: 10.1109/LEOS.1996.571601
H. Yasaka, Y. Sakai, Y. Yoshikuni
A wavelength-division multiplexing (WDM) system is a promising candidate for large capacity lightwave networks. In such a system, a frequency standard light source is indispensable to define an absolute frequency reference for WDM channel allocation. Here, we demonstrate a frequency standard light source with an arbitrary optical frequency by offset-locking it to a gas absorption line. It is also needed to allocate WDM channels at optical frequencies which are separated from the reference frequency precisely. For this purpose, we use a semiconductor mode-locked laser diode, which has multi-mode output with precise optical frequency spacings.
{"title":"Absolute optical frequency assignment in WDM network: standards and sources","authors":"H. Yasaka, Y. Sakai, Y. Yoshikuni","doi":"10.1109/LEOS.1996.571601","DOIUrl":"https://doi.org/10.1109/LEOS.1996.571601","url":null,"abstract":"A wavelength-division multiplexing (WDM) system is a promising candidate for large capacity lightwave networks. In such a system, a frequency standard light source is indispensable to define an absolute frequency reference for WDM channel allocation. Here, we demonstrate a frequency standard light source with an arbitrary optical frequency by offset-locking it to a gas absorption line. It is also needed to allocate WDM channels at optical frequencies which are separated from the reference frequency precisely. For this purpose, we use a semiconductor mode-locked laser diode, which has multi-mode output with precise optical frequency spacings.","PeriodicalId":332726,"journal":{"name":"Conference Proceedings LEOS'96 9th Annual Meeting IEEE Lasers and Electro-Optics Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114610635","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}
Pub Date : 1996-11-18DOI: 10.1109/LEOS.1996.571692
S. Chatterji, M. Fleury, M. Muendel, W. Hodge, P. Hagelstein
We have sought ways to improve the coupling of the pump laser energy to a low density plasma suitable for collisional XUV lasing. At very high intensity, laser light can be coupled directly to a low density gas through multiphoton ionization. At the intensities of our pump, the radiation must be absorbed by inverse bremsstrahlung, which is inefficient at low density. To improve the overall efficiency, an optic was designed which integrates an axicon and a reflective tube such that unabsorbed pump radiation is repeatedly refocused on axis, permitting the creation of extended line foci in gases. Experimentally it was found that 6 cm sparks could be created in 200-760 torr argon with very high pump absorption, particularly on a second, delayed pulse. To investigate the coupling of pump laser energy into the plasma column, and subsequent plasma development, a computational model has been developed. Initial plasma formation occurs as a result of multiphoton ionization. Subsequent heating of the plasma occurs by inverse bremsstrahlung absorption, while higher stages of ionization are obtained through collisional ionization. A one-dimensional three-fluid hydrodynamic model, which incorporates collisions between charged particles and neutral atoms, is used to predict plasma expansion into the surrounding gas, while the coupling of absorbed energy to the plasma front is modeled by flux-limited electron thermal conduction.
{"title":"A model for plasma formation in a reflective axicon and tube for a proposed Ne-like argon laser at 46.9 nm","authors":"S. Chatterji, M. Fleury, M. Muendel, W. Hodge, P. Hagelstein","doi":"10.1109/LEOS.1996.571692","DOIUrl":"https://doi.org/10.1109/LEOS.1996.571692","url":null,"abstract":"We have sought ways to improve the coupling of the pump laser energy to a low density plasma suitable for collisional XUV lasing. At very high intensity, laser light can be coupled directly to a low density gas through multiphoton ionization. At the intensities of our pump, the radiation must be absorbed by inverse bremsstrahlung, which is inefficient at low density. To improve the overall efficiency, an optic was designed which integrates an axicon and a reflective tube such that unabsorbed pump radiation is repeatedly refocused on axis, permitting the creation of extended line foci in gases. Experimentally it was found that 6 cm sparks could be created in 200-760 torr argon with very high pump absorption, particularly on a second, delayed pulse. To investigate the coupling of pump laser energy into the plasma column, and subsequent plasma development, a computational model has been developed. Initial plasma formation occurs as a result of multiphoton ionization. Subsequent heating of the plasma occurs by inverse bremsstrahlung absorption, while higher stages of ionization are obtained through collisional ionization. A one-dimensional three-fluid hydrodynamic model, which incorporates collisions between charged particles and neutral atoms, is used to predict plasma expansion into the surrounding gas, while the coupling of absorbed energy to the plasma front is modeled by flux-limited electron thermal conduction.","PeriodicalId":332726,"journal":{"name":"Conference Proceedings LEOS'96 9th Annual Meeting IEEE Lasers and Electro-Optics Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124708937","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}
Pub Date : 1996-11-18DOI: 10.1109/LEOS.1996.571533
R. Stultz
Presents research on Er-doped Q-switched eyesafe glass lasers. Research was done on 1.5 /spl mu/m absorption bands at intrinsic optical damage thresholds.
介绍了掺铒调q安全玻璃激光器的研究。研究了本征光损伤阈值下1.5 /spl μ m的吸收带。
{"title":"Passively Q-switched, eyesafe erbium lasers","authors":"R. Stultz","doi":"10.1109/LEOS.1996.571533","DOIUrl":"https://doi.org/10.1109/LEOS.1996.571533","url":null,"abstract":"Presents research on Er-doped Q-switched eyesafe glass lasers. Research was done on 1.5 /spl mu/m absorption bands at intrinsic optical damage thresholds.","PeriodicalId":332726,"journal":{"name":"Conference Proceedings LEOS'96 9th Annual Meeting IEEE Lasers and Electro-Optics Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123495881","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}
Pub Date : 1996-11-18DOI: 10.1109/LEOS.1996.565271
M. Nuss
Compact, practical, and cost effective femtosecond lasers are beginning to show up commercially both as solid-state and fiber lasers. These femtosecond sources can be used to great advantage in many communications and information processing applications. Interestingly enough, most of these applications are not related to the speed of these pulses, but rather use some other aspect of femtosecond laser pulses such as large spectral bandwidth, spectral coherence, intensity, short coherent length, or signal-to-noise advantages. For example, the 3 THz spectral bandwidth of a 100 fs laser pulse is wide enough to support 30 WDM channels spaced at 100 GHz, all covered by a single laser source. These channels can now be modulated using either a modulator array or even only a single modulator when the femtosecond pulses are chirped by propagation in optical fiber, as in chirped-pulse WDM. Using diode-pumped erbium fiber lasers, such a femtosecond WDM source can support many channels in a cost effective way. A single TDM modulator running at a multiple of the repetition rate of the laser can now both define as well as encode data onto the WDM channels sequentially. Interesting applications also result when we take advantage of space-time analogies in optical systems involving short pulses. This principle can be used for all-optical packet header recognition of terabit-per-second data streams. Using computer-generated holograms (CGH), we have generated and subsequently recognized 8-bit pulse sequences at a 1 Tb/s data rate.
{"title":"Information processing with short optical pulses","authors":"M. Nuss","doi":"10.1109/LEOS.1996.565271","DOIUrl":"https://doi.org/10.1109/LEOS.1996.565271","url":null,"abstract":"Compact, practical, and cost effective femtosecond lasers are beginning to show up commercially both as solid-state and fiber lasers. These femtosecond sources can be used to great advantage in many communications and information processing applications. Interestingly enough, most of these applications are not related to the speed of these pulses, but rather use some other aspect of femtosecond laser pulses such as large spectral bandwidth, spectral coherence, intensity, short coherent length, or signal-to-noise advantages. For example, the 3 THz spectral bandwidth of a 100 fs laser pulse is wide enough to support 30 WDM channels spaced at 100 GHz, all covered by a single laser source. These channels can now be modulated using either a modulator array or even only a single modulator when the femtosecond pulses are chirped by propagation in optical fiber, as in chirped-pulse WDM. Using diode-pumped erbium fiber lasers, such a femtosecond WDM source can support many channels in a cost effective way. A single TDM modulator running at a multiple of the repetition rate of the laser can now both define as well as encode data onto the WDM channels sequentially. Interesting applications also result when we take advantage of space-time analogies in optical systems involving short pulses. This principle can be used for all-optical packet header recognition of terabit-per-second data streams. Using computer-generated holograms (CGH), we have generated and subsequently recognized 8-bit pulse sequences at a 1 Tb/s data rate.","PeriodicalId":332726,"journal":{"name":"Conference Proceedings LEOS'96 9th Annual Meeting IEEE Lasers and Electro-Optics Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121662153","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}
Pub Date : 1996-11-18DOI: 10.1109/LEOS.1996.565244
M. Shih, F. Choa, T. Tanbun-ek, R. Logan, W. Tsang, C. Burrus
Coherent communication system has well-known advantages of high receiver sensitivity, high channel packing density, and flexibility in channel selection. Implementation of coherent detection in optical subscriber network for TV distribution and broad-band ISDN services have been demonstrated. Monolithically integrated coherent receivers is attractive for such applications, due to the dramatic cost reduction by eliminating packaging of hybrid components. However, the device structure as well as fabrication process of integrated receivers are usually quite complex and the yield is considerably low. We proposed and demonstrated an integrated device with simple structure can perform both transmitting and receiving functions with very high receiver sensitivity. The device structure and possible configurations as customer transceiver in coherent multi-carrier (CMC) distribution system is shown. The device is composed of a tunable DBR laser as a local oscillator (LO) and an integrated detector. This allows one to fully utilize the wavelength tuning range to achieve highly dense spaced WDM coherent systems.
{"title":"High performance integrated coherent transceivers for optical access networks","authors":"M. Shih, F. Choa, T. Tanbun-ek, R. Logan, W. Tsang, C. Burrus","doi":"10.1109/LEOS.1996.565244","DOIUrl":"https://doi.org/10.1109/LEOS.1996.565244","url":null,"abstract":"Coherent communication system has well-known advantages of high receiver sensitivity, high channel packing density, and flexibility in channel selection. Implementation of coherent detection in optical subscriber network for TV distribution and broad-band ISDN services have been demonstrated. Monolithically integrated coherent receivers is attractive for such applications, due to the dramatic cost reduction by eliminating packaging of hybrid components. However, the device structure as well as fabrication process of integrated receivers are usually quite complex and the yield is considerably low. We proposed and demonstrated an integrated device with simple structure can perform both transmitting and receiving functions with very high receiver sensitivity. The device structure and possible configurations as customer transceiver in coherent multi-carrier (CMC) distribution system is shown. The device is composed of a tunable DBR laser as a local oscillator (LO) and an integrated detector. This allows one to fully utilize the wavelength tuning range to achieve highly dense spaced WDM coherent systems.","PeriodicalId":332726,"journal":{"name":"Conference Proceedings LEOS'96 9th Annual Meeting IEEE Lasers and Electro-Optics Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121697363","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}
Pub Date : 1996-11-18DOI: 10.1109/LEOS.1996.565096
T. Higashi, T. Yamamoto, S. Ogita
Characteristics of optical sources for access networks are required to be insensitive to the environment temperature change. In a relatively long-haul (> 10 km) and high bit-rate (>100Mb/s) transmission system, the effect of dispersion of optical fiber could not be negligible. Therefore, the stability of the oscillation wavelength to the temperature change could also be required. In this paper, we experimentally examined the temperature sensitivity of the oscillation wavelength in 1.3 /spl mu/m GaInAsP-InP QW semiconductor lasers.
{"title":"Temperature sensitivity of oscillation wavelength in 1.3 /spl mu/m-GaInAsP/InP quantum-well semiconductor lasers","authors":"T. Higashi, T. Yamamoto, S. Ogita","doi":"10.1109/LEOS.1996.565096","DOIUrl":"https://doi.org/10.1109/LEOS.1996.565096","url":null,"abstract":"Characteristics of optical sources for access networks are required to be insensitive to the environment temperature change. In a relatively long-haul (> 10 km) and high bit-rate (>100Mb/s) transmission system, the effect of dispersion of optical fiber could not be negligible. Therefore, the stability of the oscillation wavelength to the temperature change could also be required. In this paper, we experimentally examined the temperature sensitivity of the oscillation wavelength in 1.3 /spl mu/m GaInAsP-InP QW semiconductor lasers.","PeriodicalId":332726,"journal":{"name":"Conference Proceedings LEOS'96 9th Annual Meeting IEEE Lasers and Electro-Optics Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122065941","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}
Pub Date : 1996-11-18DOI: 10.1109/LEOS.1996.565147
T. Matsuzono, J. Maeda, S. Kogoshi, H. Abe
We propose a novel configuration of a 2-channel WDM soliton transmission system which cancels collision-induced frequency shifts at each amplifier. We analyze its transmission characteristic numerically with regard to the varying group velocity dispersion (GVD), and predict that a 100 Gb/s/spl times/2 system utilizing 51 ps solitons amplified every 25 km maintains a BER of 10/sup -9/ over 500 km if GVD is tailored to 0.2/spl plusmn/0.08 ps/km/nm.
{"title":"Transmission characteristic improvement of two-channel wavelength division multiplexed solitons by controlling initial time offset","authors":"T. Matsuzono, J. Maeda, S. Kogoshi, H. Abe","doi":"10.1109/LEOS.1996.565147","DOIUrl":"https://doi.org/10.1109/LEOS.1996.565147","url":null,"abstract":"We propose a novel configuration of a 2-channel WDM soliton transmission system which cancels collision-induced frequency shifts at each amplifier. We analyze its transmission characteristic numerically with regard to the varying group velocity dispersion (GVD), and predict that a 100 Gb/s/spl times/2 system utilizing 51 ps solitons amplified every 25 km maintains a BER of 10/sup -9/ over 500 km if GVD is tailored to 0.2/spl plusmn/0.08 ps/km/nm.","PeriodicalId":332726,"journal":{"name":"Conference Proceedings LEOS'96 9th Annual Meeting IEEE Lasers and Electro-Optics Society","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122588065","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}
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