Pub Date : 2024-07-27DOI: 10.3103/s106833562460092x
A. I. Gorokhov, E. A. Perevezentsev, I. B. Mukhin, M. R. Volkov
Abstract
We report a developed methodology for studying the main parameters and identifying the features of chirped volume Bragg gratings (CVBGs). The results of diagnostics of the first fused silica CVBG samples inscribed by femtosecond laser pulses using a phase mask are presented: the linear absorption coefficient, phase and polarization distortions arising during grating inscription, and spectral and dispersion characteristics are studied. The results of the studies indicate the prospects for using gratings of this type in high-average-power laser systems.
{"title":"Diagnostics of First Samples of Chirped Volume Bragg Gratings Inscribed Using Femtosecond Laser Pulses","authors":"A. I. Gorokhov, E. A. Perevezentsev, I. B. Mukhin, M. R. Volkov","doi":"10.3103/s106833562460092x","DOIUrl":"https://doi.org/10.3103/s106833562460092x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>We report a developed methodology for studying the main parameters and identifying the features of chirped volume Bragg gratings (CVBGs). The results of diagnostics of the first fused silica CVBG samples inscribed by femtosecond laser pulses using a phase mask are presented: the linear absorption coefficient, phase and polarization distortions arising during grating inscription, and spectral and dispersion characteristics are studied. The results of the studies indicate the prospects for using gratings of this type in high-average-power laser systems.</p>","PeriodicalId":503,"journal":{"name":"Bulletin of the Lebedev Physics Institute","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141785596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-27DOI: 10.3103/s1068335624600864
V. P. Duraev, S. A. Voronchenko, S. V. Medvedev, M. R. Lebedev
Abstract
We report the results of fabrication works on single-frequency tunable semiconductor laser modules for a wavelength of 1550 nm, with an external cavity being based on fiber Bragg gratings formed in a single-mode fiber. Tuning of the radiation wavelength using a piezoceramic element is considered. The laser modules are capable of generating dynamically stable single-frequency radiation with side mode suppression of more than 40 dB, a lasing line width of 100 kHz, and an output optical power of higher than 50 mW. The wavelength tuning of the emission spectrum of the laser module is 2 nm.
{"title":"Single-Frequency Tunable External-Cavity Semiconductor Lasers Emitting at 1550 nm","authors":"V. P. Duraev, S. A. Voronchenko, S. V. Medvedev, M. R. Lebedev","doi":"10.3103/s1068335624600864","DOIUrl":"https://doi.org/10.3103/s1068335624600864","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>We report the results of fabrication works on single-frequency tunable semiconductor laser modules for a wavelength of 1550 nm, with an external cavity being based on fiber Bragg gratings formed in a single-mode fiber. Tuning of the radiation wavelength using a piezoceramic element is considered. The laser modules are capable of generating dynamically stable single-frequency radiation with side mode suppression of more than 40 dB, a lasing line width of 100 kHz, and an output optical power of higher than 50 mW. The wavelength tuning of the emission spectrum of the laser module is 2 nm.</p>","PeriodicalId":503,"journal":{"name":"Bulletin of the Lebedev Physics Institute","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141785642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-27DOI: 10.3103/s1068335624600876
V. I. Kozlovsky, S. M. Zhenishbekov, Ya. K. Skasyrsky, M. P. Frolov
Abstract
We report an investigation of a semiconductor disk laser (SDL) based on an InGaP/AlGaInP heterostructure emitting at a wavelength near 640 nm under in-well pumping by a pulsed rhodamine 6G dye laser with an emission wavelength of 601 nm. Use is made of structures with 25 quantum wells arranged in depth with a period of 193 nm. In a structure with a built-in Bragg mirror, a power of 3.5 W is reached at a wavelength of 642 nm with a slope efficiency of 7% with respect to the absorbed pump power. The achieved second harmonic power at a wavelength of 321 nm is approximately 30% of the maximum SDL power at the fundamental frequency. Under pumping above 250 W, the structure is destroyed due to strong adiabatic heating of the GaAs growth substrate. In a structure with a deposited broadband dielectric mirror, it is possible to reduce the adiabatic heating factor, implement double-pass pumping, and, accordingly, increase the supplied pump power. This makes it possible to obtain a pulse power of higher than 70 W at a wavelength of 645.5 nm with a slope efficiency of over 17%.
{"title":"High-Power Pulsed, In-Well-Pumped InGaP/AlGaInP Heterostructure, Semiconductor Disk Laser","authors":"V. I. Kozlovsky, S. M. Zhenishbekov, Ya. K. Skasyrsky, M. P. Frolov","doi":"10.3103/s1068335624600876","DOIUrl":"https://doi.org/10.3103/s1068335624600876","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>We report an investigation of a semiconductor disk laser (SDL) based on an InGaP/AlGaInP heterostructure emitting at a wavelength near 640 nm under in-well pumping by a pulsed rhodamine 6G dye laser with an emission wavelength of 601 nm. Use is made of structures with 25 quantum wells arranged in depth with a period of 193 nm. In a structure with a built-in Bragg mirror, a power of 3.5 W is reached at a wavelength of 642 nm with a slope efficiency of 7% with respect to the absorbed pump power. The achieved second harmonic power at a wavelength of 321 nm is approximately 30% of the maximum SDL power at the fundamental frequency. Under pumping above 250 W, the structure is destroyed due to strong adiabatic heating of the GaAs growth substrate. In a structure with a deposited broadband dielectric mirror, it is possible to reduce the adiabatic heating factor, implement double-pass pumping, and, accordingly, increase the supplied pump power. This makes it possible to obtain a pulse power of higher than 70 W at a wavelength of 645.5 nm with a slope efficiency of over 17%.</p>","PeriodicalId":503,"journal":{"name":"Bulletin of the Lebedev Physics Institute","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141778580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-25DOI: 10.3103/s1068335624600244
A. L. Shepetov, V. V. Zhukov, V. A. Ryabov, N. O. Saduev, T. Kh. Sadykov
Abstract
A system of detectors for the front of extensive air showers (EAS) was set up at the Tien Shan High-Altitude Station of the Lebedev Physical Institute (LPI), which has a high time resolution and is designed to determine the arrival directions of shower-generating cosmic-ray particles. Algorithms and software were developed for analyzing information coming from the station to obtain estimates of the azimuth and zenith angles for each registered shower. This information makes it possible to investigate a large-scale distribution of the arrival points of primary cosmic ray particles on the celestial sphere.
{"title":"Determination of Cosmic-Ray Arrival Directions Using the System of EAS Front Detectors at the Tien Shan High-Altitude Station","authors":"A. L. Shepetov, V. V. Zhukov, V. A. Ryabov, N. O. Saduev, T. Kh. Sadykov","doi":"10.3103/s1068335624600244","DOIUrl":"https://doi.org/10.3103/s1068335624600244","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A system of detectors for the front of extensive air showers (EAS) was set up at the Tien Shan High-Altitude Station of the Lebedev Physical Institute (LPI), which has a high time resolution and is designed to determine the arrival directions of shower-generating cosmic-ray particles. Algorithms and software were developed for analyzing information coming from the station to obtain estimates of the azimuth and zenith angles for each registered shower. This information makes it possible to investigate a large-scale distribution of the arrival points of primary cosmic ray particles on the celestial sphere.</p>","PeriodicalId":503,"journal":{"name":"Bulletin of the Lebedev Physics Institute","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141509031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-25DOI: 10.3103/s1068335624600360
A. G. Bagdatova, S. P. Baranov
Abstract
We discuss the suitability of few-body exclusive W boson decays for precise measurements of its mass and width. We show that the decay modes of this kind have extremely small relative widths, which excludes any possibility of their practical use.
摘要 我们讨论了少体排他性 W 玻色子衰变是否适合用于精确测量其质量和宽度。我们的研究表明，这类衰变模式的相对宽度极小，这就排除了其实际应用的可能性。
{"title":"Exclusive W Boson Decays","authors":"A. G. Bagdatova, S. P. Baranov","doi":"10.3103/s1068335624600360","DOIUrl":"https://doi.org/10.3103/s1068335624600360","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>We discuss the suitability of few-body exclusive W boson decays for precise measurements of its mass and width. We show that the decay modes of this kind have extremely small relative widths, which excludes any possibility of their practical use.</p>","PeriodicalId":503,"journal":{"name":"Bulletin of the Lebedev Physics Institute","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141515678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-25DOI: 10.3103/s1068335624600566
A. V. Shkirin, S. N. Chirikov, N. V. Suyazov, M. E. Astashev, D. N. Ignatenko, S. V. Gudkov
Abstract
The angular intensity distribution of 650 nm laser radiation multiply scattered by bovine milk samples of various fat content, containing large-scale particles with a size of ~20 μm, is studied in cylindrical geometry. It is shown that the forward scattering intensity measured for milk with a fat content in the range of 0–6% decreases monotonically with increasing concentration of somatic cells in the range of 5 × 104–106 cm‒3. However, the angular dependence of the side- and backscattering intensity, used to determine the fat content in milk, practically does not change when somatic cells are added. A prototype of a milk composition sensor is assembled, based on measuring the scattering indicatrix in the angular range of 18°–162° using an axisymmetric array of photodiodes in combination with a photodetecting CMOS matrix that measures the small-angle forward light scattering intensity (near 0°).
{"title":"Detection of Somatic Cells in Milk Using Laser Light Scattering","authors":"A. V. Shkirin, S. N. Chirikov, N. V. Suyazov, M. E. Astashev, D. N. Ignatenko, S. V. Gudkov","doi":"10.3103/s1068335624600566","DOIUrl":"https://doi.org/10.3103/s1068335624600566","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The angular intensity distribution of 650 nm laser radiation multiply scattered by bovine milk samples of various fat content, containing large-scale particles with a size of ~20 μm, is studied in cylindrical geometry. It is shown that the forward scattering intensity measured for milk with a fat content in the range of 0–6% decreases monotonically with increasing concentration of somatic cells in the range of 5 × 10<sup>4</sup>–10<sup>6</sup> cm<sup>‒3</sup>. However, the angular dependence of the side- and backscattering intensity, used to determine the fat content in milk, practically does not change when somatic cells are added. A prototype of a milk composition sensor is assembled, based on measuring the scattering indicatrix in the angular range of 18°–162° using an axisymmetric array of photodiodes in combination with a photodetecting CMOS matrix that measures the small-angle forward light scattering intensity (near 0°).</p>","PeriodicalId":503,"journal":{"name":"Bulletin of the Lebedev Physics Institute","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141515683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-25DOI: 10.3103/s1068335624600062
P. Yu. Apel, M. M. Chernyavsky, A. A. Gippius, G. V. Kalinina, N. S. Konovalova, N. M. Okateva, N. G. Polukhina, Zh. T. Sadykov, T. V. Shchedrina, N. I. Starkov, E. N. Starkova, I. I. Zasavitskii
Abstract
The first results of testing KU-2 optical quartz glass as a detector of accelerated heavy ions are presented. The results of etching the irradiated glasses in hydrofluoric acid indicate a possibility of their use for detecting superheavy nuclei and their decay products.
{"title":"Study of Etching Features of Quartz Glass Irradiated with Xenon Ions","authors":"P. Yu. Apel, M. M. Chernyavsky, A. A. Gippius, G. V. Kalinina, N. S. Konovalova, N. M. Okateva, N. G. Polukhina, Zh. T. Sadykov, T. V. Shchedrina, N. I. Starkov, E. N. Starkova, I. I. Zasavitskii","doi":"10.3103/s1068335624600062","DOIUrl":"https://doi.org/10.3103/s1068335624600062","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The first results of testing KU-2 optical quartz glass as a detector of accelerated heavy ions are presented. The results of etching the irradiated glasses in hydrofluoric acid indicate a possibility of their use for detecting superheavy nuclei and their decay products.</p>","PeriodicalId":503,"journal":{"name":"Bulletin of the Lebedev Physics Institute","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141509029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-25DOI: 10.3103/s1068335623600018
A. I. Nikishov
Abstract
The author compares, in the Born approximation, the cross sections for graviton scattering on Newtonian center in three cases using 1) a three-graviton vertex of general relativity, 2) a vertex formed with a properly chosen gravitational energy-momentum tensor of a massless spin-2 field, and 3) a vertex formed with Landau and Lifshits pseudotensor energy momentum. In all three cases, the cross sections are different For scattering by angles θ of an order of unity. So, in principle, the experiment decides which three-graviton vertex is used by nature. The manifestation of nonlocalizability of field energy is noted.
{"title":"On Possible Three-Graviton Vertices","authors":"A. I. Nikishov","doi":"10.3103/s1068335623600018","DOIUrl":"https://doi.org/10.3103/s1068335623600018","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The author compares, in the Born approximation, the cross sections for graviton scattering on Newtonian center in three cases using 1) a three-graviton vertex of general relativity, 2) a vertex formed with a properly chosen gravitational energy-momentum tensor of a massless spin-2 field, and 3) a vertex formed with Landau and Lifshits pseudotensor energy momentum. In all three cases, the cross sections are different For scattering by angles θ of an order of unity. So, in principle, the experiment decides which three-graviton vertex is used by nature. The manifestation of nonlocalizability of field energy is noted.</p>","PeriodicalId":503,"journal":{"name":"Bulletin of the Lebedev Physics Institute","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141509030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-25DOI: 10.3103/s1068335623601735
R. Jyothilakshmi, S. Sandeep, Yu. A. Mityagin, M. P. Telenkov, K. K. Nagaraja
Abstract
Aluminum nitride, a promising piezoelectric material grown below 400°C that is CMOS compatible, can be used for wide piezo applications. In this work, AlN is deposited using reactive magnetron sputtering at sputtering temperature of 300°C. Our focus was to grow c axis-oriented AlN thin-films at relatively low sputtering power for piezoelectric application. In this direction AlN thin films were deposited at a low sputtering power of 100 and 125 W and at a sputtering temperature of 300°С. X-ray diffraction and atomic force microscopy techniques were used to characterize the structural and surface topography of deposited thin films. Films grown at 125 W have a highly c axis-orientation (002) plane with an FWHM value of 0.38°. The roughness of the films was found to be 7.00 Å, and the near zero skewness represents a symmetric roughness distribution in the films. Pure films of this phase can be used for device applications in the future.
摘要 氮化铝是一种有前途的压电材料，其生长温度低于 400°C，与 CMOS 兼容，可用于广泛的压电应用。在这项工作中，氮化铝是在 300°C 的溅射温度下使用反应磁控溅射法沉积的。我们的重点是在相对较低的溅射功率下生长出面向 c 轴的氮化铝薄膜，用于压电应用。为此，我们在 100 W 和 125 W 的低溅射功率以及 300°С 的溅射温度下沉积了氮化铝薄膜。X 射线衍射和原子力显微镜技术用于表征沉积薄膜的结构和表面形貌。在 125 W 条件下生长的薄膜具有高 c 轴取向 (002) 平面，FWHM 值为 0.38°。薄膜的粗糙度为 7.00 Å，接近零的偏斜度代表了薄膜中对称的粗糙度分布。这种相的纯薄膜将来可用于设备应用。
{"title":"An Investigation of the Structural and Surface Topography of Aluminum Nitride Thin Films Deposited at Low Sputtering Power for Piezoelectric Applications","authors":"R. Jyothilakshmi, S. Sandeep, Yu. A. Mityagin, M. P. Telenkov, K. K. Nagaraja","doi":"10.3103/s1068335623601735","DOIUrl":"https://doi.org/10.3103/s1068335623601735","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Aluminum nitride, a promising piezoelectric material grown below 400°C that is CMOS compatible, can be used for wide piezo applications. In this work, AlN is deposited using reactive magnetron sputtering at sputtering temperature of 300°C. Our focus was to grow <i>c</i> axis-oriented AlN thin-films at relatively low sputtering power for piezoelectric application. In this direction AlN thin films were deposited at a low sputtering power of 100 and 125 W and at a sputtering temperature of 300°С. X-ray diffraction and atomic force microscopy techniques were used to characterize the structural and surface topography of deposited thin films. Films grown at 125 W have a highly <i>c</i> axis-orientation (002) plane with an FWHM value of 0.38°. The roughness of the films was found to be 7.00 Å, and the near zero skewness represents a symmetric roughness distribution in the films. Pure films of this phase can be used for device applications in the future.</p>","PeriodicalId":503,"journal":{"name":"Bulletin of the Lebedev Physics Institute","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141515680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-25DOI: 10.3103/s1068335624600050
A. N. Lykov, I. A. Lykov
Abstract
We report calculations of current‒voltage characteristics (I‒V characteristics) of Josephson junctions using the resistive model. The I‒V characteristics are found to be stable to deviations of the dependence of the superconducting current on the phase difference (φ) of the order parameter at the junction boundaries from the simple sinusoidal one, characteristic of ideal Josephson junctions. It is shown that to analyze the processes occurring in Josephson junctions, it is important to measure the spectral composition of generation from these junctions.
{"title":"Current‒Voltage Characteristics of Nonideal Josephson Junctions","authors":"A. N. Lykov, I. A. Lykov","doi":"10.3103/s1068335624600050","DOIUrl":"https://doi.org/10.3103/s1068335624600050","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>We report calculations of current‒voltage characteristics (I‒V characteristics) of Josephson junctions using the resistive model. The I‒V characteristics are found to be stable to deviations of the dependence of the superconducting current on the phase difference (φ) of the order parameter at the junction boundaries from the simple sinusoidal one, characteristic of ideal Josephson junctions. It is shown that to analyze the processes occurring in Josephson junctions, it is important to measure the spectral composition of generation from these junctions.</p>","PeriodicalId":503,"journal":{"name":"Bulletin of the Lebedev Physics Institute","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141515679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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