| dc.contributor.advisor | 陳洋元 | zh_TW |
| dc.contributor.advisor | Chen, Yang-Yuan | en_US |
| dc.contributor.author (Authors) | 李彥濬 | zh_TW |
| dc.contributor.author (Authors) | Li, Yen-Jun | en_US |
| dc.creator (作者) | 李彥濬 | zh_TW |
| dc.creator (作者) | Li, Yen-Jun | en_US |
| dc.date (日期) | 2018 | en_US |
| dc.date.accessioned | 6-Aug-2018 18:13:33 (UTC+8) | - |
| dc.date.available | 6-Aug-2018 18:13:33 (UTC+8) | - |
| dc.date.issued (上傳時間) | 6-Aug-2018 18:13:33 (UTC+8) | - |
| dc.identifier (Other Identifiers) | G0105755001 | en_US |
| dc.identifier.uri (URI) | http://nccur.lib.nccu.edu.tw/handle/140.119/119216 | - |
| dc.description (描述) | 碩士 | zh_TW |
| dc.description (描述) | 國立政治大學 | zh_TW |
| dc.description (描述) | 應用物理研究所 | zh_TW |
| dc.description (描述) | 105755001 | zh_TW |
| dc.description.abstract (摘要) | 氮化鈮是一種低壓縮性與高硬度的材料，它擁有多種不同的相結構，包括立方晶系的δ- Cubic相、四方晶系的tetragonal相與六方晶系的δ’- hexagonal相和ε- hexagonal相。在我的研究中，探討每個相所存在的超導性質。其中，立方晶系δ-相的粉末樣品是從Alfa Aesar這間公司購得，藉由攝氏一千四百度的退火過程得到的產物。而此立方晶系δ-相的粉末樣品再藉由X光繞射分析儀的數據得知，晶格常數為4.385 Å。藉由電阻、磁化率的量測可以知道立方晶系δ-相的超導溫度為13.4K，這與文獻上描述超導溫度是晶格常數的方程式是一致的。另一批樣品是由Goodfellow這間公司所買來的粉末所製備，經由熱處理希望得到ε- hexagonal的純相。Zou et. al.他們這團隊在一篇文獻上描述到氮化鈮有兩個超導臨界溫度，分別為立方晶系δ-Cubic相的17.1K與六方晶系ε-hexagonal相的10.1K。為了要驗證ε- hexagonal是否擁有超導特性，我們從未經過熱處理的Goodfellow粉末中挑選出顆粒，進行拋光後，利用EBSD量測其結構，結果顯示ε-hexagonal結構。並對它進行電阻的量測，在電阻對溫度的關係中，呈現出的是金屬性的行為，並且在量測到最低溫2 K時，依然沒有出現超導的特徵。經過熱處理的Alfa Aesar粉末首先壓成塊狀，並且量測它的比熱行為。觀測到的超導轉變溫度Tc 13 K。根據BCS理論的計算，超導體電子比熱部分ΔC/γTc值是1.43，而我們的計算結果為0.82，結果指出並不是常規的超導性質。接著將樣品量測不同溫度底下的磁化率隨磁場變化，並計算出Hc1是185 Oe；不同磁場底下的電阻隨溫度變化，並計算出Hc2是19.22 T。最後從這批粉末中挑出塊才樣品，經過拋光後量測EBSD的結果為δ- cubic，經過電阻量測後，顯示出超導行為超導轉變溫度Tc 13 K，並且量測計算出Hc2是21.3 T，結果與壓成塊狀的C(T)以及R(T)一致。 | zh_TW |
| dc.description.abstract (摘要) | Niobium nitride is a low compressibility and high hardness material. It has many phases structures, including cubic δ-NbN, ε-hexagonal, δ’-hexagonal and tetragonal. In this work, we investigate the appearance of superconductivity of each NbN phase. Pure cubic δ-NbN specimens were prepared by annealing 1400 oC from NbN powder of Alfa Aesar. The lattice constant of this specimen was determined to be 4.385 Å by powder X-ray diffraction (XRD) measurement. Superconductivity of Cubic δ-NbN phase was revealed at 13.4 K by the measurements of resistivity magnetic susceptibility and heat capacity of pressed powders. It is consistent with previous reports that Tc is a function of lattice constant. Zou et. al. reported that two superconducting temperatures of 17.1 K and 10.1 K appear in the powder of Goodfellow, they claimed 17.1 K is of cubic phase and 10.1 K is of ε-hexagonal phase. We also observed two Tc from the powder of Goodfellow, based on X-ray and magnetic data the Tc =17.1 K is defined from cubic phase, but the phase of Tc =10.1 K is hardly fitted to the ε-hexagonal phase. In order to check whether ε-hexagonal phase have superconductivity or not, a sub-micron particles of single crystal was selected from the powder of Goodfellow, the ε-hexagonal phase of the particle is revealed by the measurements of EBSD (Electron Back Scattering Diffraction). The resistivity measurement of the sub-micro crystal shows no superconductivity as temperature down to 2 K.We also measured the specific heat of cubic NbN from pressed powder of Alfa Aesar. The superconductivity transition temperature Tc =11 K was observed. The electronic part of specific heat, ΔC/γTc is equal to 0.83 which is lower than BCS value, 1.43, indicating an unusual superconductivity. The critical field of superconductivity Hc1 obtained from the magnetic field dependent magnetization is 185 Oe. The Hc2 obtained from magneto resistivity data is 19.22 T. A sub-micron size δ-cubic crystal successfully selected from Alfa Aesar powder was confirmed by EBSD, Tc=13 K and Hc2 =21.3 T were obtained from resistivity measurements, the results are in consistent with that obtained from χ(T) and R(T) of the pressed powder specimen. | en_US |
| dc.description.tableofcontents | Abstract I摘要 III致謝 IV目錄 V圖目錄 VIII表目錄 XII第一章 緒論 11.1 研究背景與動機 11.2 Niobium Nitride物理特性簡介 11.3 超導現象與特性簡介 3第二章 實驗基本原理 42.1 超導現象理論 42.1.1 BCS理論 42.1.2 邁斯納效應(Meissner effect) 42.1.3 第一類超導與第二類超導 42.2 電阻、電導(鍵結與作用力) 62.2.1 凡德瓦爾力(Van der Waals’ force) 62.2.2 離子鍵(Ionic bond) 62.2.3 共價鍵(Covalent bond) 62.2.4 金屬鍵(Metallic bond) 62.2.5 金屬性與半導體性電阻與溫度關係 72.3 磁化率(Magnetic susceptibility)與居禮常數(Curie constant) 82.4 四點量測(4-probe measurement) 92.5 單晶(single crystal) 92.6 基本繞射原理(Diffraction) 102.6.1 單狹縫繞射 102.6.2 雙狹縫繞射 112.6.3 布拉格繞射(Braggs law) 112.7 比熱原理(Specific Heat) 132.7.1 聲子比熱 132.7.2 電子比熱 13第三章 實驗製備與儀器 143.1 樣品相結構量測 143.1.1 粉末X光繞射(Powder X-ray diffraction, XRD)量測 143.1.2 電子背向散射繞射儀(Electron back-scatter diffraction, EBSD)量測 153.2 樣品磁性、電性量測 183.2.1 超導量子干涉儀(Superconducting quantum interference device, SQUID) 183.2.2 物理性質量測系統儀(Physical property measurement system, PPMS) 193.3 比熱量測 213.4 高壓磁性 223.4.1 High pressure cell結構與原理 223.4.2 壓力計(鉛、錫、銦)校正 23第四章 實驗結果與分析 244.1 XRD擬合結果與磁化率比對 244.2 EBSD結果(ε-hexagonal) 294.3 EBSD結果(δ-cubic) 334.4 ε-hexagonal相PPMS數據分析 394.4.1 電阻與溫度關係 394.4.2 電阻與磁場關係 454.4.3 量測完檢討 454.5 δ-cubic相PPMS數據分析(Sample 1) 484.5.1 電阻與溫度關係 484.5.2 改變電流下電阻與溫度關係 534.5.3 改變磁場下電阻與溫度關係 554.5.4 電阻與磁場關係 574.5.5 量測完檢討 574.6 δ-cubic相RT數據分析(Sample 2) 584.7 比熱量測 624.8 改變壓力下磁化率與溫度關係 68第五章 結論 73參考文獻 75 | zh_TW |
| dc.format.extent | 3831068 bytes | - |
| dc.format.mimetype | application/pdf | - |
| dc.source.uri (資料來源) | http://thesis.lib.nccu.edu.tw/record/#G0105755001 | en_US |
| dc.subject (關鍵詞) | 氮化鈮 | zh_TW |
| dc.subject (關鍵詞) | 超導 | zh_TW |
| dc.subject (關鍵詞) | 相 | zh_TW |
| dc.subject (關鍵詞) | 微米晶體 | zh_TW |
| dc.title (題名) | 氮化鈮微米晶體的相與超導性研究 | zh_TW |
| dc.title (題名) | Phase and superconductivity studies of micro-sized niobium nitride | en_US |
| dc.type (資料類型) | thesis | en_US |
| dc.relation.reference (參考文獻) | [1] Solid State Communications 149 (2009) 725-728[2] Springer Handbook of condensed matter and materials data, Part 4|2.1, page 704[3] Zou, Y. et al. Hexagonal-structured ε-NbN: ultra-incompressibility, high shearrigidity, and a possible hard superconducting material. Sci. Rep. 5, 10811; doi: 10.1038/srep10811 (2015)[4] ISSN 1061-3862, International Journal of Self-propagating High-Temperature Synthesis, 2010, vol.19, No.1, pp.9-16[5] V. Buscaglia et al. / Journal of Alloys and Compounds 266 (1998) 201 –206[6] Materials Chemistry and Physics 141 (2013) 393-400[7] Zou, Y. et al. Discovery of Superconductivity in Hard Hexagonal ε-NbN. Sci. Rep. 6, 22330; doi: 10.1038/srep22330 (2016)[8] 中山文庫 <<低溫.超導.磁浮>> 何健民[9] PHYSICAL Review B 83, 144525 (2011)[10] Journal of Applied Physics 47, 2833 (1976)[11] 工業材料雜誌 201期 92年9月[12] Oxford Instruments Nanoanalysis Mar 3 2015[13] Journal of Applied Crystallography ISSN 0021-8898, 1968[14] PHYSICAL REVIEW B 80, 134514 2009[15] Appl. Phys. Lett., Vol. 60, No. 13, 30 March 1992[16] IEEE Transactions on Applied Superconductivity ( Volume: 17, Issue: 2, June 2007 )[17] R. Sanjine´s et al. / Thin Solid Films 494 (2006) 190 – 195[18] Journal of Applied Physics 40, 2153 (1969)[19] Received 2 June 1980. in final form 20 October, 1980[20] J Sanchez-Benitez et al. J. Phys.: Conf. Ser. 121 122001, 2008[21] R Cabassi et al. Meas. Sci. Technol. 21 035701, 2010[22] PHYSICAL REVIEW B 75, 174502 (2007)[23] Solid State Physics, Ashcroft Neil W.[24] CeRu2的奈米為結構與物性研究, 林宗立[25] Bi2Te3塊材與奈米微粒之熱電效率、熱傳導率與比熱之物性研究, 陳志挺[26] 量子尺寸對鉭的超導性與晶體結構之影響, 陳志文[27] CeRu2塊材與奈米微粒之超導與磁性研究, 黃紹哲[28] C.Kittel, Introduction to Solid State Physics (Wiley, United States of America, 1996)[29] Rev. Sci. Instrum., Vol. 72, No. 7, July 2001[30] H. Wang, M. Sen / International Journal of Heat and Mass Transfer 52 (2009) 2102–2109[31] LOW TEMPERATURE PHYSICS VOLUME 27, NUMBER 9–10 SEPTEMBER–OCTOBER 2001[32] Superconducting properties and Hall Effect of epitaxial NbN thin films, S P Chockalingam, India[33] Effect of nitrogen to niobium atomic ratio in superconducting transition temperature of δ-NbN, powders, 2009 | zh_TW |
| dc.identifier.doi (DOI) | 10.6814/THE.NCCU.AP.002.2018.B04 | - |
